Purpose

The digital switchover is the UK telecommunications industry’s replacement of the ageing analogue Public Switched Telephone Network (PSTN) and ISDN with internet-based digital services, such as Voice over Internet Protocol (VoIP). The transition is already underway and BT plans to retire its PSTN by 31 January 2027, by which point affected Council lines and dependent devices must have been migrated, replaced or safely ceased. The Council has a fragmented legacy fixed-line telephony and broadband estate of 651 lines across six providers, with a current cost of approximately £17,493 per month and £209,916 per year. Analysis has taken place with respect to the use of the lines many of which are legacy in nature and with no clear ownership. This work has identified that 67 are confirmed for migration, 7 are already migrated to digital services, 36 are school-managed, 69 have already been ceased and a further 215 are safe to cease and 93 remain unresolved, where the phone rings out, but is not picked up and / or the line is incurring call charges.

There are a further 164 lines for which no data can be found. The phone does not ring and there are no call charges – the proposal is that these lines are ceased following a final attempt to contact the service owner. This will be a ‘soft cease’ which gives 30 days grace before full removal. A prudent planning ceiling of 200 PSTN lines has therefore been set to transfer from the existing analogue service to a new digital provision. This is a maximum number and does not mean that all 200 lines will be migrated: only lines confirmed as operationally necessary through the discovery and validation process will move to the new service, other lines will be ‘soft ceased’ as per the approach above. For the retained lines, the recommended decision is to use the Council’s existing Gamma and Microsoft Teams telephony capability as the default destination for validated corporate voice requirements, while running a controlled discovery and cessation programme for all other records. NOTE: This is not a blanket replacement of legacy lines. Broadband, alarms, lifts, fire and security systems, and other analogue or safety-critical devices will be managed through separate specialist workstreams. Adults’ services have confirmed that there is no dependency on PSTN lines for any telecare or telehealth services. This proposal focuses on the IT migration to digital and does not analyse call charges due to the nature of the federated solutions procured by each of the directorates; each area has different billing arrangements. The call charges are often in pence so no notable saving is likely to be realised, but after the migration we will work with Gamma to further analysis the call volumes and make future strategic recommendations as appropriate. Approval is sought for an initial implementation envelope of up to a maximum of £108,150 comprising a prudent ceiling of 200 number ports and 120 physical Teams phones. Recurring phone line charges are forecast at £8,400 per year (£3.50 per line per month). Expenditure will be released only against validated records and confirmed unit rates. Broadband lines costs are forecast at £67,645 in total, considering the updated technology and based on rates from current providers (the 196 broadband lines will see an anticipated 25% increase in current costs). There is likely to be an opportunity to analyse and optimise these broadband links following migration, to reduce costs.

The current total cost of lines and Broadband is £209,916 which post migration will run at a reduced cost of £67,645. The total implementation costs will be £108,150. Based on the analysis performed to date, the project will soft cease lines for which no owner can confirm requirements, communications will be issued across standard channels (intranet, email, teams sites, etc.) and owners will have 30 days before the line is removed. Cost reduction and benefits assurance Previous analysis identifies 256 records already on a cease path with £69,287 in annual cost. These savings remain a validation target until invoices confirm that charges have ended. The proposed £108,150 approval ceiling is deliberately prudent and does not declare that 200 lines are required. The programme is intended to reduce the final migration volume through discovery and cessation. The recommended approach also controls operational risk. Ordinary voice numbers will be migrated only after ownership and use are confirmed. Any alarm, lift, fire/security, broadband or other specialist dependency will be separated from the voice requirement and routed to an appropriate replacement or controlled-retention workstream.

Decision

1. Approve the existing Gamma and Microsoft Teams telephony platform as the default corporate destination for validated standard voice requirements arising from the PSTN exit. 2. Approve the controlled cessation (soft cease with 30-day termination) of redundant services and the phased migration of required numbers, with no blanket commitment to replace all remaining records. 3. Approve a maximum initial planning envelope of 200 number ports and 120 Teams phones, comprising up to £108,150 in one-off costs and recurring annual costs of £8,400 for Telephone lines and £67,645 for Broadband.
   

Alternative options considered

1. Do nothing / leave carriers to migrate services Rejected. This creates a high risk of service interruption, uncontrolled provider-led replacement, continued fragmented billing and missed cessations. 2. Replace every non-ceased line like for like Rejected. This would treat uncertain, redundant and non-voice records as required services, locking in avoidable cost and risk. 3. Procure a separate corporate voice platform A separate procurement would duplicate an existing strategic capability and create mobilisation risk. Commercial have confirmed that we can leverage the current contract with Gamma.