Without speaking on when it should have happened, IE have BT made mistakes?...., from my experience it reflects once a bill is generated, so if it wasnt added at the 'right' time and now it has.....then I think you will have to wait until the next one is generated, you may need to ignore the next bill estimate as it wont reflect upcoming credit. At least this is what happened to me, credits and adjustments were applied to a bill as some minus figure to offset what I owed rather than an 'account balance' as such, like when your electrical bill is in credit.
When I joined BT my account ended up in a complete mess and it took one person about 3 months to sort it out form a billing point of view, credit was applied nearly every month to offset fee's that actually it wasnt even clear where they had come from.
When I was with Vodafone I racked up some £100-200 compensation due to a failed install, again with them I was unable to just have this money to spend whilst I was still a customer, however after getting so livid with them I left within my cooling off period and they actually then bank transferred me the outstanding compensation.
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BT900 | Nokia ONT | Ubiquiti ER-X | EETV Box Pro (IP Mode) | Unifi CK2 | 6x Unifi U6+ | 2x Unifi SAK Ultra
