BACS Services for HMRC

Background
His Majesty's Revenue and Customs (HMRC) is the UK's tax, payments and customs authority and collects the money that pays for the UK's public services and gives financial support to people.
HMRC is a direct submitter to BACS, leveraging BACS-approved software and providers to submit. HMRC are seeking to engage interested providers in the market who are BACS-Approved Software (BASS) providers and who are able to provide Bacstel-IP services.
For the purposes of this PIN, HMRC Commercial are representing HMRC's interests, but are also considering the longer-term implications of Unity in delivery. The Unity programme is a major cross-government programme centred on building shared service capability to modernise and standardise ERP systems across three government departments: HMRC, Department for Transport, and Ministry of Housing, Communities and Local Government.
DfT and MHCLG are not direct submitters to BACS and instead use a bureau service to submit payment files to BACS. This is currently provided by PayGate and is due to expire in April 2028.
It is currently envisaged that procurement for the new BACS contract(s) will launch per the timescales provided below within this document.
This Prior Information Notice (PIN) is issued for notification purposes and does not constitute a formal tender or pre-qualification process, nor does it represent a commitment to procure any goods or services.
Parties should note participation in pre-market engagement will not influence or provide advantage in any future procurement, and that the scope, services, values and timelines referenced are indicative only and subject to change.
Note the procurement may not go ahead in this and/or any format, and any procurement is subject to relevant internal approvals.
PIN objectives
The purpose of this updated PIN is to:
a) advise the banking industry that HMRC intend to undertake a tendering exercise to award new contract(s) for the provision of BACS;
b) provide further...