Feels like yesterday
So, I got the Celebi quest, knocked off the first three items pretty fast, and started on the second page. Got my 3 new friends, evolved a Weepinbell into a Victreebel, and caught a wild Pokemon.
Today, I caught a quest reward pokemon. Now, I'm feeling just like I did on Sunday, and Monday before the quest opened. Can't do anything, waiting until midnight so I can catch another quest reward and proceed. A bit frustrating, and it seems like Niantic is using a kind of artificial means (catch on three days) thing to slow down the quest. (Yes, I know, it comes up a second time later in the quest chain.)
Just venting a little bit here.
Answers
Well, I won't specifically confirm or deny anything officially here, but I've just moved on to part 3 of the quest. Thanks, gluglumaster.
Additionally, on the last day of the month, I'm traveling, and I was worried about getting my 5th Raikou (I currently get my 7th stamp on Saturdays. Now I can use this trick and get the 7th stamp before I go on the trip and make sure I get another Raikou instead of a Suicune (ugg) or Entei (not as bad).
In my head you're essentially taking the next day's stamp/pass in advance. Today's the 21st, if I get my stamp/pass for the day then change the date to the 22nd and use tomorrow's stamp/pass I won't get anything when the 22nd actually rolls around. I say this as someone who's never messed with the date/time settings, having been shadowbanned once for using a shitty IV checker has made me skittish about messing with the game like that.
Personally I like it. During the work week I couldn't complete the entire questline in a day anyway so them forcing us to wait for the next step feels just fine to me. Now I can plan ahead to get my 9 eggs to hatch just after midnight tomorrow when I get my 3rd day catch, then walk the Espeon and Umbreon the next day and get to the next time-gated part.