Yes they have but seems like most earlier orders are shipping already, mine hasn’t changed yet, hopefully soon, I returned a 2019 MBP 13” that I had for only a week to order this one.
Oh wow - our situations are very similar lol. I ordered a 2019 MBP on April 29th. It arrived on May 1st. I returned it on May 4th when the 2020s were announced. Had to wait for the refund to hit my account (it hit earlier this AM) to order the 2020.
I hope yours ships ASAP!