Recently got the AS visa, was going to pay rent with it this month to hit the sub.
I approved only what I would for the rent payment on the Bilt card (rent +some to cover the $5 handling fee). Got an two emails simultaneously (date and time are identical)

• "There was an issue with your rent payment"
• "Your BillPay rent payment has processed"
  • the body of this email says "your payment [...] is processing"

Anyway, I realized I didn't authorize enough to cover the transaction fee. I assume this payment would fail otherwise. I figure that because the transaction fee is charged by Bilt that it wouldn't need to be part of the authorized amount.
Switched back to the Bilt card to avoid NSF issues before the payment is tried again tomorrow. Will try again next month with the AS card and larger amount.