When to start countdown

Super excited to start my 12/12 cycle tmrw but dont know when the actual countdown starts for flowering. I have a 60 day strain . So is it 60 days from the time switch or 60 from the time they start to bud?

It is not an absolute and the days are always wrong, no matter when you start counting. I'd say "after stretch" but in two months, you want to be watching trichromes to see when ready.

I always start counting immediately after the flip. But it always seems to take 5 to 10 days longer than breeders recommendation. Sometimes even longer especially with autos. Just get a loupe and watch the trichomes. Theyll tell you when shes ready.

I haven't bothered to count in years.......Breeder reports are always wrong......always longer and you get a better product by running longer too.
Just starting out? Simply mark on a calendar the day you flipped.....at 7 weeks later start looking closely.....I'll bet there is 2-3 weeks left from there.

Doc

It isn't an exact date.

Once your buds start getting orange hairs and swell up you can check once a week with a x60 magnifier for maturity of trichomes.

DON'T SQUEEZE YOUR BUDS. That damages the trichomes and can make them look amber.

Flowering time from the breeders is always an estimate.

The mother might be a 10 week strain and the father could be a 8 week strain. They take an educated guess for their info.

In reality the seeds could all have differing harvest times. Maybe 1 at 8 weeks and 2 at 9 weeks and even 1 at 11weeks.

Go to the breeders estimate and then start scoping the trichomes. Check once a week until ripe.