The lifetime for new authorizations has been decreased, see this post for details. I think it might be something like 30 or 60 days right now, it’ll probably be something like 7 days eventually.
Basically, you’ll need to be prepared to solve a new challenge for each renewal. Perhaps you can use something like acme-dns to automate the DNS challenge in your environment, if you feel like that’ll save time compared to doing it manually once every 3 months.