Yeah, each season, the requests reboot.
Much like every few months, you can ask for a new feeder team, the request for a new stadium restarts.
I've found that if you ask at the start of a season, then you'll have to wait until about mid-Jan.
Now, if you remaining expansion capacity, then they should say "plans are afoot to expand the stadium"
At this point, you'll want to match the capacity of the stadium to the potential capacity.
I forget the exact term, but look up a few posts, the exact explanation is there.
The date should get to about May or June and they'll either grant the stadium or again say "due to strong opposition from local council......."
If you've saved it before this date, then go back and change your attendance to something ridiculous.
Max, Average and Minimum don't apply. But actual attendance, seating and expansion capacity should be changed to something stupid like 500 (BUT capacity used, I put to 400 just to be on the safe side as I'm not entirely sure what effect that would have).
The news story then goes from "strong local council blocks planning permission" to "Board announce plans for a new stadium."
My stadium is bizarrely (despite min attendance being 30000) a 28500 seater (when Ashton Gate is 29000) and costs 70m. Also takes a year to build