Capital One looks at history of spend and payments
A
If you do 10k at a time and pay it off at once, and do it a couple of times
- then check for 15k a day or two later, it often allows that charge next
you can work it up to 20
B
Another option is to send 5k to it from your bank account to the card first - Effective limit goes to 15k = x6 is 90k done
(it is not as good as Amex which often allowed me to spend 120k on a Delta Reserve last year with a 5k line by paying ahead)
or send 10k spend 20k - pay off 10k (in fact I think cap1 allows payments above balance - so you can pay off 20k - do it daily x 5 days
C
what is the hurry - you can do 6x10k now and 4x 10k in July - within 6 months = bonus done
The IRS limits credit card tax payments to 2, so it won't work.