I usually top when my plants have 5 or six leaf sets but I don’t try to clone that cutting. I suppose you could try it. I take my cuttings from weaker side branches that don’t look like they will thrive. When I tried this, I waited until the clones showed roots out of the bottom of the seedling trays they were in(like I said, probably 2 tblsp of soil). Once I saw the roots, I flipped them to flower lighting. All told, it was about a month from cutting to showing sex(2 weeks to root, 2 weeks to show-might be a bit more or less). So I would try to get the cuttings taken about 5 weeks prior to flipping your keepers to flower so you have a week for the plants to recover from transplanting to the final pot. I wasn’t on a schedule when I did this so I didn’t need to time it but I think that should work. Unless you are going straight from the solo cups to the final pot. This method probably won’t work for that as your solo cups would be pretty root bound if you wait to show sex on the clones…