[big al]

Cheques can be cashed for up to six months officially. Banks check aprox 1 in ten cheques for accuracy max as so many go through the clearing houses it is imposible to check every one. All cheques can be passed over for banking into another account as long as the payee has signed the back as a waiving of their right to present & cash the cheque.
If you are normally paid by cheque for wages then why not ask your employer to pay you directly by BACS which is a safe electronic payment without use of the post. No excuse then for "It's in the post mate."