In Yubeng, we stay at Lobsang Trekker's Inn (香巴拉雪域 if I remember the Chinese correctly). The owner said Yubeng is currently open to tourists.

There's certainly plenty of places around Shangri-La. Here's a few I just asked today. This is our place: www.gokunming.com/[...]

These places both said they can receive foreigners:
www.gokunming.com/[...]

www.gokunming.com/en/listings/item/34062/yis-hostel

香格里拉唻桑卓康客栈 (ctrip search is easiest).

I'll post again if I hear anything about Yubeng.

Nice to read this thread as we're considering doing this soon. Does anyone have experience in the last year or so? I've heard it's possible they do not allow Chinese cars into Thailand anymore. Could this be accurate? If that is the case, has anybody who's taken this route have an opinion if there would be a safe place to park a car and then take a bus for the Thailand portion?

I started brewing last year at 3300m in Shangri-la. I don't know enough yet to comment about altitude, but you could hook up with the guys in this gk articlewww.gokunming.com/[...]

Maybe you're on your trip already. I don't know about other places, but there are night buses between Kunming and Shangri-la. I was just through Pudacuo again last weekend. Much quieter, but on a sunny day still quite pleasant.