payment by bank cheque - how long to encash

[TheTheory]

Dear experts,

If you pay your immigration fees/RFPR/ect... using bank cheque, which is payable for "The Receiver General for Canada", how long does it take to confirm payment, and do they issue receipt immediatly at designated embassy, or do they have to send it to canada for processing? ususally when your bank issue a bank cheque, the correspondence is a canadian bank, so do they send cheques to canada or they just confirm payment locally if embassy is outside canada???