I recently got upgraded to grade 5 on my account and not even 12 hours has passed, im suddenly back to grade 4. I left the game earlier after a couple of touch and goes, and i remembered that i had 201 (90 days) landings. And i check back right now and its at grade 4 @ 199 landings.
2 of your landings were 91 days ago, therefore they do not fall into the category of “90 Days”, therefore dropping your “Landings In The Past 90 Days” count and dropping you below the minimum grade 5 requirement.
2 Landings/Touch-and-Goes and you’ll be back at Grade 5.