Don’t go by the breeders suggestion you’ll sell yourself short. Most autos, in my experience go 75-90 days. Make sure you either have a jewelers loupe to check trichs or a usb microscope. Trichs will tell you when they’re done.
I do have a USB microscope I'll keep a close look out. And I hope it's not 75-90 days I'm excited to see the harvest. But time will tell and mine will go that long like yours. Just to make me watch and wait! LOL