when to chop?

Hey mate, It especially depends on how you flush. If you use an finish or clean additive it will cut a couple days of flushing. But a relatively rule would be flush at least 5/7 days before you harvest (depends on the size of the buds). That gives the plants some time to throw out all the salt and minerals build up in the buds. What will give you an harsh smoke. In your case I would wait at least 7 days after flush, unless you use an additive like flawless finish. The stress your plants will get by cutting the top should not be a problem, it could even make the lower buds bigger and more resinous. I hope this helped you to make decisions!😉 Try out how to handle this with fun, because that's what an harvest should be! 😁 Good luck🤙🏼