FWIU from BAHayman is that it's not a server issue that can be easily solved by moving the site elsewhere as he has done in the past for us but a bug in the php script that's acts up on occasion and is very hard to pinpoint. It drives CPU levels from 50-75% up to 400% which is when people get the 502s.
If anyone knows any troubleshooters for such an issue I'm all ears. In the meantime his tweaks have definitely improved the situation over the past few weeks.