[gobyebye]

Ive been told that when changing climates(bringing plants from veg room to flower room)
you need to let the plants acclimate for a couple days to a week. apparently theres a huge shock to the plant when changing the environment, and doing this before flipping them into bloom,also another shock, can cause unwanted stress

[lost in a sea]

depends on how different your rooms are really..

There is a bit of shock from the higher day time temps suddenly (bigger temp swings) and increase in moles of light but that is natural to an extent as environmental stressors and triggers do help induce flowering and ripening. what would be more natural inside would be to do like many do and to decrease the hours from 18/6 to 12/12 over 2 or 3 weeks or longer..

there isn't much else about the environment that should be that different between your grow room and flo room. A lack of air turnover would but that should be better in your flower room unless maybe you release co2 in which case the change in air pressure could maybe stress them a bit, i do and i've not seen that cause trouble yet ..

[Farm Hero]

I let em go two weeks after transplanting.... one week for acclimation and one week to ease the hours down to 11/13

[Douglas.Curtis]

As lost in a sea pointed out, it depends on how large a difference there is between the rooms. Personally, I veg under bloom lighting intensities because it creates the plant strength needed for bloom. Even then, I generally veg at least a week under the light I'll be blooming with.

Differences in light spectrum/intensity, RH, temp highs/lows/cycles and airflow will all be things the plant should be adapted to, before flower.