Unable to create CT600 for remaining accounting period only (duplicate period issue)

I have already submitted a Corporation Tax return (CT600) directly to HMRC for the period:
29 December 2023 to 31 January 2024.

I now need to submit the remaining Corporation Tax return for the following period only:
1 February 2024 to 31 Jan 2025.

However, when creating a new submission in TinyTax, the system automatically detects an extended accounting period (29 December 2023 to 31 December 2024) and splits it into two CT600 returns. This would result in a duplicate submission for the period that has already been filed with HMRC.

Could you please advise how to:
- Create a CT600 submission for a custom accounting period (1 February 2024 to 31 Jan 2025) only, or
- Exclude the already submitted CT600 (29 December 2023 to 31 January 2024) from the automatic split?

This is my company’s first year, and the issue is caused by HMRC splitting the first accounting period.

Thank you for your help.