Also spoke briefly on the Off-White x Jordan 4s. Stock varies by how many physical locations each store has but a safe number is 100 pairs per major location that a store has.
I expect most boutiques to have a couple hundred at best in sizes up to 12W. Very few will get above 12W. Your odds of getting a pair go drastically down after 10W. 10.5+ is going to be the most expensive and most limited.
This stock is about double that of Travis Scott SB but I still expect Nike to directly keep the most of it on SNKRS like they did for OW5s.
I do not expect many, if any at all, do online FCFS drops outside of SNKRS and Off-White. Will know more next week