Hi there, Timp11. In QuickBooks Online (QBO), there is no option to do a two-month period when filing your taxes.
The available filing frequency options in the program are limited to Monthly, Quarterly, Half-yearly, and Yearly. Since a two-month filing period is not supported, I recommend contacting HMRC directly for specific guidance on how to proceed. They will be able to advise you on the appropriate steps to ensure compliance.
Please let us know if you have further concerns by replying to this thread.