I have existing cards with bofa and chase with credit lines of about 4,000 each, both of which I've had for a few years. I signed up for two cards today from these banks for sign on bonuses and both gave me a credit line of about 17,000 each.

I would like my existing cards to have a matching credit line so it can lower my overall credit utilization.

I understand that if you do two credit card apps at the same bank on the same day they combine into one hard check. But does this still apply to a credit increase and a credit card app?

Before applying for the two new cards credit karma showed 0 inquiries through TransUnion and 1 from Feb '16 through Equifax.