I figure this is boarderline OT but would have the greatest target audience here. So hope it can stay here for a while.
Anyway, i'm on my En Premieur spree and was told I cannot temporarily increase the credit line on both the BA AMEX and the SPG AMEX (UK). have anyone tried to do this before? I've never encountered this before when I was HK based. in fact many card issuers would never mind if i did this!

They only offered me to bank them at my basic green card which i am reluctant...