Date for ILR application

Hi all
I’m British and my wife is Moroccan and we are on a 5 year route for ILR. We are currently in the second 2.5yr period and my wife BRP expires in September 2024. We married in April 2019 and her first BRP was issued in sept 2019.
Prior to applying and being on the spouse visa route my wife was in the U.K. for a number of years on a tier4 visa. So once married (April 2019) we applied for spouse visa.
My question is when can we apply for ILR? I know you can apply 28days in advance, so:
1. Can we apply in March 2024?
2. We have to wait to August 2024?
Hope this makes sense.

Her qualifying period starts when her spouse visa was granted, not the date you got married.

She can apply for ilr no sooner than within 28 days before the 5th anniversary of her spouse visa issue date. So yes, she has to wait till August/September before she can apply.