This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Oil Taxation Manual

PRT: administration: decisions - claim period in dispute

Where what is in dispute is not the question of expenditure and supplement but the claim period in which the expenditure was incurred, then, if the company has provided all the information required, the Inspector will, on request, disallow the expenditure rather than win the argument by default by deferring a decision. This will apply particularly where accruals are being examined.