Seems a few of us are having issues with Pioneer wireless CarPlay with random disconnects. For me, it did it every few minutes, so it was completely unusable. At this point, I don't know whether to blame Apple or Pioneer in case Pioneer has done a dodgy implementation of it.
There was a USB wireless CarPlay adaptor that's been posted not far back, and so far there are three of us, including me, using it, and so far it's working flawlessly on my 17 PM. It's not disconnected once in weeks as I've disabled the native Pioneer wireless CarPlay and I'm just using the adapter. It’s ridiculous that we need to buy it, but at least it’s a pretty cheap fix.
I’m also starting to think it’s a Pioneer issues. Thanks for the reply. I’m going to try the dongle now.