upon re-reading their rules, maybe it was not a change

rules

says
Walk in permits
are issued starting at 11 am one day before the trip entry date. If space is still available, permits can be issued on the day of the trip.

Reserved Permits
"You must pick up or confirm your reservation before the deadline or the reservation will be canceled. Deadline for overnight permits is 10 am on the entry date.

so our recent walk-in, day-of, overnight permit success at 9:05am on a midweek Wednesday might have been (A) a " virgin" permit still available from 11 am the day-before until ?? 11 am the day-of rather than ( B) an unclaimed (or reduced party) reserved permit which would not have become available until after 10:00 am the day-of. Ranger did not say which source our permit came from. Hard to imagine that in August their were any from group (A) but maybe so.