Yeah, I agree that is too fast. Some people aren't on every day.
You don't need to be on every day. That tournament had 6 days between creation (18th) and being started (24th). It may have been that there was not long between being sent a pm about joining and the actual start, but it is demanding for tournament host to have to write to everyone to join their tournaments, and especially for tiebreakers like this time is important - it is holding up the league. I know it is hard to see tournaments if playing mostly on a phone but this just not make it someone else's responsibility to get a person to join. To me, someone sending a message telling people to join is a service, not an entitlement.
