When I placed the order, the expected arrival time was around the end of March / beginning of April. Near the end of March, it updated to be around the end of May, and a couple weeks ago, it updated to Jun 2 to Jun 17 as the arrival window, which is where it remains as of now (April 25th).
The issue seems to be supply chain disruption, especially in the wake of China's Zero Covid policies. I customized the order, including with 64GB of RAM, which Googling suggests is delayed in particular.
If I decide to cancel the order before the resolution time, I'll resolve as N/A. Otherwise I'll resolve once I have it, or the deadline has passed.
May 17, 9:58am: It now says it will ship on May 26th!
💬 Proven correct

Daniel Reeves bought M$15 of YESa month ago
Useful question to pose! I ended up getting a refurbished one, in part because I could get it the next day. I think the refurbished ones Apple sells -- https://www.apple.com/shop/refurbished/mac -- are as good as new, but, alas, nothing with 64GB of memory seems to be available that way.
Daniel Reeves made M$8!

Adele Lopez is betting YES at 93% 2 days ago
Got it!

Adele Lopez is betting YES at 80% 8 days ago
Estimated delivery is now May 23rd!

Daniel Reeves bought M$15 of YESa month ago
Useful question to pose! I ended up getting a refurbished one, in part because I could get it the next day. I think the refurbished ones Apple sells -- https://www.apple.com/shop/refurbished/mac -- are as good as new, but, alas, nothing with 64GB of memory seems to be available that way.