Last time somebody did this to me there were a lot of sit downs about how to properly chop up large scale code changes and why we don't sit on our own branch for two months.
"How long will this take to get in?"
"Well, two weeks for me to initially review it, a week for you to address all the changes, then another week or so for me to re-review it... Then of course we have to merge in all the changes that have been happening in primary..."
Last time I got this PR I was like, "Okay, I'll do my best, but you asked the guy that has like 30 mins a day to actually focus and look at someone else's code AND yours isn't the only PR I'll have to look at this sprint. Have fun reminding me about this for the next week."