you can top sooner than lst. but if you lst too early it realyl doesn't do much but can definitely shock the plant. you bend it over with a few growth nodes and usually the lowest is trash anyway, so where is this growth being spread out?
I liked to have more than just a nub for axilay buds before i bend it over. tiny with a hint of leaves is better and a little more growth even better than that.
anchor the bottom. bend 45 degrees between axes of growth nodes and you can use both sets instead of cutting off the downward facing ones. As long as the plant hasn't gotten woody / rigid, it's not too late and no loss for waiting unless it's overgrown at that point, of course.
tbh, in your space with that many plants... i'd top after 4-5 nodes, prune off the lowest 2 branches as they usually are trash. and just train the remaining 4-6 branches to grow evenly and you will have a packed tent and all plants can grow symmetrically and fit well. should do well either way. you may need to splay out the top most branches until the lowers catch up, then you can let it go vertically all together. by that time they should be out a ways from central area, which will be a good thing. interloc that growth between pots.