What size to flower?

I started a wide variety of strains in soil.Some are over 1ft tall the 2 clones are 1.5ft and flowering ang I have compact mature flower ready plants and about 3 or 4 that are from 2in. to 4 in. high.Should I change the light cycle to flowering now and sacrifice the late germinators? the othe plants are like 2ft. from the light.

Hopefully you have lots of light power for all those plants. No one can give you any advice without knowing what you plan to throw at 'em.
Running plants of different sizes and different ages can give ya a headache.

You're not going to be keeping an even canopy that's for sure may want to top some of the taller plants I'd probably top twice give the little ones a chance to catch up cause they'll just produce fluffy shit mostly too far from the light but best would be to have a veg room too but sounds like you don't.

Like blunt says top the big yins and stick some old books under them or something to raise the smaller one's to roughly the same height.......