2' tall you should do pretty well, they won't grow that much more before you will see signs of the start of flowering. You may want to put them into bigger pots, this would be a good time to do this. It really depends on what you are growing as to the yield, have you topped them or supercropped them at all. Topping them will help them bush out and could be beneficial with the yield if they veg for a while longer. I would just fim them, cut or top them but just take the top 1/2 inch or so off. In conclusion you are definitely not too late moving outside and having them 2' tall won't hurt you either. Just as a guess you should get at least an ounce off of each plant if they are receiving plenty of sun and you feed and water them regularly. When are you getting out? Just kidding, I like Marc as well
Watch for bugs on your plants, most can be dealt with by hand. Keep them happy and they will keep you happy, I hope all is well with you and yours
mal