FYI - HMRC Employment History for SMP, SPP, SSP periods

Useful info if it helps you --

HMRC issued 'employment history' only lists 'earned' wages, and taxes thereon. If you were paid SMP, SPP or SSP, it might be a good idea to get a letter from your employer showing your leave summary, although this would also be corroborated by the payslips.

Better to have the information and not have to use it, than to not have it at all.

The term / name "employment history" is a misnomer. What one is asking for and is receiving is a "income and tax history" and one cannot expect HMRC to provide details of SMP/SPP/SSP because these are constituents of the "pay" an employer pays an employee.