Tandem are changing the connected banks number to just ONE single account.
Unless you tell them which one to use, they will default it to the last one that you used, or one with a regular payment.
Check your emails if you have a Tandem account.
Mine has a tenner in, so not too fussed tbh
BBC News - Bank of England cuts interest rates to 4.25% - BBC News
Bank of England cuts interest rates to 4.25% - BBC News
Banks will quickly reduce rates on savings accounts but take ages to increase them if the base rate went up.
BoE drop the rate by 0.25pp, so what do Atom do?
Standard saver drops 0.35pp
Reward Saver withdrawal rate drops by 0.50pp
Never saw them raise rates by more than the BoE change 
That is unfortunately the business model for many new digital banks now like Chase, Chip, Atom, etc.
They launch with promotional rates to get new customers in, then they gradually reduce the rate below the BoE rate, cutting a bit extra each time, hoping people don’t pay close attention or aren’t bothered to move their cash.