If you've got two feet to go, you may not have an issue. I had the same worry a week and a half ago, when my 2.5 footer reached 4.5 feet at 2 weeks of flower.

Luckily, it seems to have stopped at just shy of 4 weeks. Currently the top is 6 inches under the hood glass, and has been there a few days.

Unfortunately it's a strain thing in many cases. So yours could be different.
Vancefish Reviewed by Vancefish on . skunk too big! hi all, i'm currently 2 weeks in flower and one of my babies is getting dangerously close to my light. i've got 2 x lemon skunk, and 2 x blue cheese under a 400w hps in a 75x75x1600 budbox. 1 of the plants is 12" taller than the others, but they all started at the same time! i've got 6 weeks of flowering remaining, and about 2' of space for it to grow into. my question is, if i really have to top it or tie it down, which will cause the least amount of stress to the plant. Rating: 5