HMRC are reminding traders to prepare for customs changes that come into effect on 1 January 2022. You will no longer be able to delay making import customs declarations under the Staged Customs Controls rules that have applied during 2021. Most customers will have to make declarations and pay relevant tariffs at the point of import.
You should consider before 1 January 2022 how you are going to submit your customs declarations and pay any duties that are due.
If you want to use Simplified Declarations, you will need authorisation to do so. It can take up to 60 days to complete. Therefore a new application made now may not be authorised before 1 January 2022.

For a summary of the changes see: GOV.UK (www.gov.uk)