If he can do his 50 amendments in their allotted time he can amend all he wants to but at the end of their 24 hours they are DONE!!!
The amendments do not count against the time allotted to Opening Arguments, as far as I can tell. In fact, I don’t see anywhere they are limited, other than 1 hour debate for each side. If Schumer intends to burn up days and weeks arguing amendments and rules, I hope Mitch cuts him off tomorrow.