EM8312 - Companies: Quarterly Instalment Payments: Timing of Enquiries
The earliest date at which enquiries into the proper payment of instalments can be made is the statutory filing date for the company’s return. There is no latest date. This means that it would be possible to seek information under Regulations 10 and 11 after the CTSA enquiry window for the relevant return had closed.
You should not use regulations 10 and 11 to extend the CTSA enquiry window in this way. As instalment payments are (or should be) made before the return is filed, you should normally be able to judge long before the enquiry window closes whether you need to check the instalment payments position.
If, exceptionally, you consider you need to use regulations 10 and 11 after the relevant CTSA enquiry window has closed, you should make a report with your file to contact link before issuing a notice.