There is no in-store process as they won't have them available until next week. But once Apple Store receives them in stock then that will change. I too, have ordered the AirPods with the wireless charging case and mine is also set for March 27 - 29.Ordered the updated AirPods with the wireless charging case and received email confirmation on March 20, 7:18 AM MDT. There was no in-store pickup option. March 27-29 is the current ETA, Order in Progress.
I did exactly the same thing. I hope these AirPods have Bluetooth 5.0. I don't care about the color at all, pointing out to the rumors of future AirPods or the past rumors regarding AirPods 2.I ordered the version with the wireless charging case (in case iPhone 11 comes with power share feature lol). It says 26-28 March (UK).
Be sure to check FedEx, too... at least in my area, release day iPhones and Watches come UPS, but almost everything else that I get from Apple comes FedEx.PFS! Hoping to find it on UPS tomorrow and I hope we all get then Monday/Tuesday since there's no street date on them