Went to Memorial Hermann ER uninsured. How long does it take to get a bill?

I'm hoping I just got really lucky and the ER staff was really nice, or that my issue wasn't worth charging, as I logged into their patient portal and saw no bill.

IIRC seeing my PCP (while insured) would result in a bill the same day, but obviously these are two different situations.

If anyone has had this experience, should I expect a bill on the portal or in the mail within the month? Or have I been blessed with a kind act?