The CT600 Company Tax Return Guide for box 471 reads as follows 471 CJRS received
Enter the total amount of Coronavirus Job Retention Scheme (CJRS) payments you received, in the accounting period covered by this return.
When calculating the amount received, you should not deduct:
• amounts which have been voluntarily disclosed to HMRC as CJRS overpayments, whether repaid or not;
• any amounts that have already been assessed by HMRC, whether the assessment is paid or unpaid.
• amounts you received that you were entitled to but repaid voluntarily
Add back any overpayments of amounts received in an earlier period that have been offset against CJRS payments received in this accounting period.
You can access the CT600 Guide at:
COMPANY TAX RETURN GUIDE