I can confirm that adapter is still working for me, I've driven for over an hour in total with this adaptor, using Waze and streaming lossless music at the same time, still wearing my Ultra 3 unlocked and this adapter hasn't disconnected once.
I'm using it with an aftermarket Pioneer SPH-360DAB headunit and my 17 PM seems very happy with this combo so far. I can't say for 100% certainty this adapter would work for everyone but for me it's been perfect.
I bought this one. It's one of those devices that might show up in many different names, but as long as it looks the identical, it's most likley the same one.
Wireless CarPlay Adapter
www.amazon.co.uk