No, not at all. She looks big enough to flower.
I grew some a couple of years ago and they were a little smaller when I started 12/12 and they grew to around 31" so, I thought so but, just wanted soon advise.
you can flip to flowering schedule at anytime. its all up to personal preference on how big you want them to get that will determine on when you flip.
Depending on when you’re leaving in July and your plant may not be completely flowered by then