My user writes:
"I have a meeting that I scheduled on March 11 from 1:00-3:00. It is for
a large group of people.

Originally I had scheduled this time frame for us as "Tentative". I was
holding space to plug in a meeting once things were confirmed. We have
confirmed this date and I edited the meeting and re-sent it back out to
the group. I changed the subject line, added body copy, and changed it
from "Tentative" to "Busy".

However the meeting is still showing as "Tentative" on all our
calendars. But, I noticed if I try to Edit the meeting again (like I am
going to make changes) it is set at "Busy". This is a confirmed meeting
and I would really like it to show as Busy on all of our calendars. Any
idea of what may be causing it to show incorrectly on our calendars even
though I updated and changed it?"
The documentation suggests that because the change did not involve date,
time, or place, users would not have been prompted again to accept it.
That makes sense. It would have been good to get the "show appointment
as" part to change, though.

I went to the sender's calendar and changed the meeting there to display
as "busy" but that did not change it on any other calendar.

This may not be something that is done a whole lot, so maybe it's just
"one of those things" and not worth looking into. But if anyone can
tell me whether this is working as designed or is a small bug, please
chime in!