Recently attempted to file a Corp Tax Return in respect of the year ended 31.3.19 with a AIA claim of approx £ 244 K via 3rd Party Software.
HMRC issued a rejection notice ( code 9288 ) on the grounds that " the sum of boxes 690 & 735 must not exceed the apportioned AIA limit". As the apportioned limit for the year is £ 400 K, I fail to see this reasoning. The Software provider is of the opinion that HMRC has not as yet reflected this change within their systems - an issue confirmed on the HMRC Web-Site - " The Corporation Tax On-line service will be updated to reflect this change in May '19"
Anyone had experience of this, as HMRC have had over 6 months to amend their systems.