My company is applying for an outward TT. Can my boss sign on the application form? For amendments, can my boss sign on the amendment form?

Only the account Authorised Signatory(s) is / are allowed to sign on the TT application form, subjected to account signing conditions, if any.

This is the same for amendment form. However it is not necessary for the original signers who have signed off on the TT application, to sign on the amendment form, as long as they are the one of the authorised signatories (subjected to the account signing conditions).