galaxy Z fold 3 out of stock?

Right now, supply chain management is more voodoo than it is software and science.  It's hard to get allocation, manufacturing by everyone is delayed, there are shortfalls in many common materials, and then the ports are overloaded.

In the same way that you cant walk into a store like you used to and have 25 different multi-function laser printers in every conceivable manufacturer and form factor, getting phones across many different colors, models, variations, etc, is a bit difficult.

I doubt very much that even if we had the T-Mobile VP of supply chain on this thread right this second that even that person would know the answer themselves.  They would probably tell you exactly where in the chain they have several thousand units on order but no idea when they would clear [insert step here] because of [politically correct term for COVID uncertainty].