You should check all applications for clearance as soon as you
receive them. Any queries you have should be raised with the
taxpayer straight away even though it may be clear from the file
that the application is premature (
IHTM40051) and it could be some time
before you will be able to issue the certificate (IHTM40121).
If it is not possible to issue the certificate straight away you should explain to the taxpayer why not.