WHD how it works

Hi this might be obvious but not to me! I’ve just been awarded the WHD can anyone tell me how this will work. ie will bulb use this for my next payment?

The payment gets added to your Bulb account.

Indirectly it won’t replace your next payment but possibly will assist in you reducing your monthly direct debit payments or in some instances may be able to be refunded to you (via your bank) if you have built up sufficient credit.