🏢 The Business
A logistics and warehousing company based across three sites in the West Midlands — a head office in Wolverhampton, a distribution centre in Walsall, and an admin office in Stourbridge. Staff count: 45 across all sites. They had been BT ISDN customers for 12 years.
⚠️ The Problem
The company received a BT letter notifying them of ISDN withdrawal from their exchange. They were paying £340/month across the three sites for 6 ISDN channels and 3 direct lines. Call quality was good but the system was inflexible — transferring calls between sites required an external transfer (the sites weren't connected), and remote workers had no way to use their office extension.
🔍 Site Survey Findings
Telexico conducted a survey of all three sites. Key findings:
- Head office: BT FTTP already installed — VoIP-ready. Had a 12-year-old Panasonic PBX that was IP-capable (SIP-compatible).
- Walsall distribution centre: Still on FTTC. Needed FTTP upgrade for reliable VoIP. Also had a very old BT Merlin PBX — not SIP-compatible.
- Stourbridge admin: Already had CityFibre FTTP. Panasonic system similar to head office.
| Site | Action Required | Timeline |
|---|---|---|
| Wolverhampton HQ | SIP trunk to existing Panasonic PBX | Week 1–2 |
| Walsall DC | FTTP upgrade + new hosted VoIP handsets | Week 3–6 |
| Stourbridge Admin | SIP trunk to existing Panasonic PBX | Week 1–2 |
🔄 The Migration Approach
For the two Panasonic sites, Telexico deployed SIP trunks — preserving the existing PBX infrastructure and minimising disruption. For Walsall, where the old PBX wasn't SIP-compatible, a full hosted VoIP deployment with new Yealink IP handsets was recommended.
Critically, all three sites were connected into one phone system — internal extension dialling between sites, one auto-attendant, and call recording across all lines. This was impossible to achieve on the previous separate ISDN connections.
✅ Go-Live and Outcome
| Metric | Before | After |
|---|---|---|
| Monthly phone bill | £340 | £195 |
| Inter-site calls | Chargeable | Free |
| Remote worker extensions | 0 | 8 staff on mobile app |
| Call recording | None | All calls recorded |
| Monthly saving | — | £145/month |
The migration was completed in 6 weeks with zero disruption to business operations. Both the Walsall FTTP upgrade and the SIP trunk configurations at the other two sites ran in parallel, and the old BT lines were kept in service until go-live day.
Have a multi-site phone system challenge? Telexico surveys and migrates businesses across the Midlands and North.
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