Not sure about others but in my case the points were revoked within 24 hours (next business day). Might be a possibility your account will go through a review process and AMEX will decide to revoke the 60,000 bonus. Be sure to keep a close eye if you chose to take the risk of not putting in the additional $500 so that you can ensure you get the minimum spend.

Regarding airline credit reimbursement I think this one is YMMV as the two agents I spoke with over the phone did quote them as one of the few reimbursements that supposedly - and incorrectly - pushed me below $5K. The big one for me was a DL reimbursement after I cancelled a trip within the 24 hours window. DL is a little weird, rather than not collecting the charge like AA does they actually collect the fare and reimburse.