i would explain any large movements of money on your bank statements in your letter of support, saying you've paid a loan and a CC off, thou it would have been better not showing any statements with large deposits or withdraws.
yes you should be ok to send 3 of one of them, as long as you have 6 statements of the other account, you only really need to supply statements for 1 account, but if you've got 2 showing a good balance then
i never sent a CC statement, i even used my credit card to transfer £5k to my current account, then transferred the debt to my other CC which had 9 months interest free for CC transfers, got my 6 banks statements, then paid the CC off with the money
just need to plan, but some people don't
