EXCEL – Split Remaining contract value over financial years

I have a spreadsheet with total contract values – Contract start date – How long is left in months

I need to know how much money we will earn from the contract value for each financial year (1st april start)

[Excel image](https://i.stack.imgur.com/i7heO.png)

I need to minus the invoiced off the contract value – split the contract value remaining across each financial year depending how long is left
Example shows 15 months remaining – 15 per month
need to know how much we would earn -arpil 2022 -arpil 2023 -april 2024 -april 2025 – april 2026 etc depending when contract ends

Report is 11k lines long 🙁

Can anyone help with the formula

Tried a few different formulas but need it as 1 entire formula if possible