How long?

How long after you flip to 12/12 do you start seeing flowering? It's been a week and a couple days.

Depends if they are ready to start budding. How long did you veg I have a variety of girls all vegged in different length and I tried to force flower a big bud and it vegged for 3 weeks and it started showing pistols 2 weeks after all the others

you mean to see buds forming?
or do you mean to see pistols?

Week to 10 days you should start to see pistils. Hopefully you dont see little tiny balls
.....Nobody much likes little tiny balls.

I saw pre-flower signs within 3 days with my strain. You should start seeing signs within a week of the 12/12 light cycle. Some plants need to grow to a certain extent or enough growth to trigger their flowering stage. either your plant hasn't matured enough or you have a light leak. Either factor is preventing your plant from flowering.

Thx man I'll investigate