Why not keep your business up to date with Network Rail’s Procurement Pipeline by visiting the following page https://www.networkrail.co.uk/industry-and-commercial/supply-chain/procurement/
On the same page you will also be able to view Network Rail’s CP7 Capital Delivery Procurement Plan Presentation. Although its dated back to Jan 2022 the plan does give some useful insights into each of Network Rail’s Regions and timeline frames on when they will be hoping to implement various CP7 project works https://www.networkrail.co.uk/wp-content/uploads/2022/02/Capital-Delivery-CP7-Procurement-Plans-January-2022.pdf
We would however, recommend that you follow each region for more specific tender deadlines and anticipated project start dates as these differ across the regions.
Other very useful information you will find on this page is their contracts register and RISQS codes.