I have done a search and cant see this having been brought up but apologies if it has....im considering taking the recent email offer and getting one of these but in the email it says an assumed credit limit of £1200. If im using the 2-4-1 companion voucher, what if the flights i am buying are more than that and i dont have another Amex to pay the difference on. Will this make it ineligible ?

Also....if im paying say £3000 for flights on BA and want to use £1200 on the amex card and the rest on another card, is this possible to use 2.....and a further complication, is it possible that i could put 1200 on, pay it off immediately, put another 1200 on, pay it off immediately then pay the final 600 again......boosting me towards the £10k ??

Thanks in advance and apologies again if this has been answered.