Client Case Study

From Dark Hours to 24/7 Coverage: How AI Voice Agents Transformed a Retail Chain's Customer Support

A UK multi-site retailer was losing revenue and customer trust every night and weekend when phone support went offline. Within 8 weeks, AI voice agents were handling 100% of out-of-hours calls — without a single new hire.

64%
Calls Resolved by AI
24/7
Inbound Coverage
3.1x
ROI Within 6 Months
8 wks
From Enquiry to Live
Prepared by
Erhan Timur, Founder
www.digitalbydefault.co.uk
Confidential
April 2026
Ref: CS-VAI-2026-04
The Challenge

Phone support went dark every evening and weekend — costing revenue and customer trust

When the Head of Customer Service at a UK retail chain with 38 locations reached out to Digital by Default, the problem was clear and urgent:

I'm a Head of Customer Service at a retail chain and our phone support goes dark on nights and weekends. Which AI voice solutions provide real 24/7 inbound coverage without hiring additional agents?
Head of Customer Service, UK Retail Chain (38 stores)

The business was experiencing a cascade of interconnected problems, each compounding the next:

Operational Pain Points

  • 76 hours per week with no phone coverage — every evening after 6pm plus full weekends
  • Monday morning backlogs of 200+ voicemails, taking the team until Wednesday to clear
  • 23% of weekend callers never called back, representing lost revenue on high-intent purchase enquiries
  • Store managers fielding calls on personal mobiles, creating compliance and data protection risks

Business Impact

  • £18,000+/month in estimated lost sales from unanswered out-of-hours calls
  • Negative reviews citing “impossible to reach” and “no one answers” on Google and Trustpilot
  • Staff burnout — senior agents covering weekend shifts on rotation were leaving within 6 months
  • Hiring additional agents for nights and weekends would cost £85,000+/year (minimum 3 FTEs)

Why “Just Hire More People” Wasn't the Answer

The client had already explored traditional outsourced call centres. Quotes came back at £6,800–£9,200/month for basic after-hours cover, with no product knowledge, 4–6 week onboarding, and no integration with their existing CRM or inventory systems. Call quality scores from trial periods were 40% below in-house benchmarks.

Discovery

What we found during the audit

Before recommending any solution, we ran a 5-day discovery sprint analysing the client's call data, support workflows, and customer journey:

Digital by Default · Case Study CS-VAI-2026-04 · Confidential
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The Solution

An AI voice agent stack purpose-built for retail inbound support

We designed and deployed a production-grade voice AI system using best-in-class components, fully integrated with the client's existing infrastructure:

Layer Technology Role
Orchestration Cognigy.AI Conversation flow management, intent routing, multi-turn dialogue, CRM/inventory integration via API
Speech-to-Text Deepgram Nova-2 Real-time transcription with retail-specific vocabulary model, <300ms latency
Text-to-Speech ElevenLabs Turbo v2 Natural-sounding brand voice, cloned from the client's top-rated support agent
Knowledge Base RAG (Pinecone + GPT-4o) Product catalogue, returns policy, store info — updated nightly from the client's PIM
Telephony Twilio SIP Trunk Existing phone numbers preserved, seamless handover to the AI agent after hours
Workflow n8n (self-hosted) Escalation triggers, CRM ticket creation, SMS confirmations, analytics pipeline

Why this stack — and not the alternatives

We evaluated four leading platforms against the client's specific requirements. Here's a summary of our recommendation rationale:

Platform Strengths Verdict
Cognigy Enterprise telephony, multi-language, deep CRM integrations, omnichannel Selected
Ada Native Shopify/SFCC integration, strong chat; voice still maturing Shortlisted
Voiceflow Excellent visual builder; better suited to smaller-scale voice bots Considered
Sierra AI Premium brand-voice agents; pricing prohibitive for 38-store scale Considered
Implementation

8 weeks from first call to live deployment

1

Weeks 1–2: Discovery & Call Data Audit

Analysed 4,200 call recordings, mapped the top 12 intent categories, defined escalation rules and success metrics with the client's CS leadership team.

2

Weeks 3–4: Voice Agent Build & Brand Voice

Designed 5 core conversation flows, built the RAG knowledge base from product/policy docs, cloned the brand voice using ElevenLabs from recorded sample calls (with agent consent).

3

Weeks 5–6: Integration & QA

Connected Cognigy to the client's CRM (HubSpot), inventory API, and Twilio SIP trunk. 380+ test calls across all intent categories. Escalation routing validated with live agents.

4

Weeks 7–8: Soft Launch & Go-Live

Week 7: AI handled calls 6pm–9pm only (shadow mode with human backup). Week 8: Full 24/7 deployment across all 38 store phone lines with real-time monitoring dashboards.

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The Results

Measurable impact within the first 90 days

Key Performance Metrics (90-Day Average)

64%
Calls Fully Resolved
by AI (No Human)
11s
Average Wait Time
(Down from 2m 40s)
4.6/5
Post-Call CSAT
(Up from 3.8)
£14.2k
Monthly Savings
vs Outsourced Cover
0%
Missed Calls
(Down from 100% OOH)
3.1x
ROI Achieved
Within 6 Months

What the numbers mean in practice

Revenue Recovery

Weekend callers asking about product availability were now answered immediately. The AI agent checks live inventory, confirms stock at the nearest store, and can send a Google Maps link via SMS. Saturday conversion from phone enquiry to in-store visit increased by 31%.

Monday Morning Transformation

The voicemail backlog disappeared entirely. Monday mornings went from 200+ messages to an average of 12 escalation tickets — pre-triaged, categorised, and with full transcripts attached in HubSpot.

Agent Experience

Human agents now handle only the calls that genuinely need empathy and judgement — complex complaints, VIP customers, and nuanced returns. Agent satisfaction scores rose from 6.2 to 8.4 out of 10 and weekend shift attrition dropped to zero.

Compliance & Data Protection

Store managers no longer field calls on personal mobiles. All calls are recorded, transcribed, and stored in compliance with UK GDPR. The audit trail alone justified the investment according to the client's DPO.

We went from dreading weekends to forgetting they were ever a problem. The AI handles the routine calls so well that some customers don't realise they're not speaking to a person. And the ones that do? They don't care — because they got their answer in 30 seconds instead of leaving a voicemail and waiting until Monday.
Head of Customer Service, UK Retail Chain (38 stores)
The team at Digital by Default didn't just deploy a tool — they understood our customers, our product catalogue, and our brand voice. The AI sounds like us because they took the time to make it sound like us.
Chief Operating Officer, UK Retail Chain
Digital by Default · Case Study CS-VAI-2026-04 · Confidential
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What Happened Next

Phase 2: From out-of-hours to always-on AI copilot

Following the success of the after-hours deployment, the client expanded the AI voice agent into business hours as a first-line triage layer. The system now:

Ongoing Support & Optimisation

Digital by Default provides monthly optimisation reviews: analysing call transcripts, tuning intent models, updating the knowledge base, and A/B testing new conversation flows. The AI gets measurably better every month. Resolution rate has climbed from 64% at launch to 71% at the 6-month mark.

Is This Right for You?

This solution is a strong fit if…

  • You have no phone coverage outside business hours
  • 60%+ of calls are routine and repetitive
  • You're losing customers to voicemail or abandoned calls
  • Hiring night/weekend staff is cost-prohibitive
  • You need calls integrated with your CRM and inventory
  • You want to preserve your brand voice, not sound like a generic bot
  • You care about UK GDPR compliance and audit trails
  • You want results in weeks, not quarters

Let's explore what 24/7 AI voice coverage could look like for your business.

Book a free 30-minute discovery call. No pitch decks — just an honest conversation about your call volumes, your pain points, and whether AI voice is the right fit.

Book Your Discovery Call →

About Digital by Default

Digital by Default is a London-based AI automation consultancy that builds production-grade AI systems for businesses ready to move beyond experimentation. From voice AI and intelligent chatbots to workflow automation and AI governance, we deliver measurable outcomes — not transformation theatre.

Services include: AI Voice Agents · Chatbots & Virtual Agents · Custom AI Agent Development · RAG & Knowledge Base AI · Workflow Automation · White-Label AI SaaS · AI Strategy & Training · AI Governance & EU AI Act Compliance

Digital by Default · Case Study CS-VAI-2026-04 · Confidential
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