Increasing light in last 3 weeks of flower-will it help bud size?

[Agen36]

Hi, I've got a much more powerful light than I normally use arriving today.

Should I use it on a plant with about 3 weeks left before harvest (hoping to improve bud size) or on a much younger plant still in veg?

Which initial use would be more effective?

 

[bigjack]

Changing things late in flower would worry me about stressing the plant and causing herm issues.

 

[Antics]

It could help IMO, and this also works: LA's Quick Guide To Simple Backbuilding Technique For Buds!

 

[Agen36]

Probably should have mentioned the light is an LED from Advanced, the Diamond series-I'm replacing my HPS. Has great user reviews-hoping I love it also.