OK Bungie, this may be something you want to add to your troubleshooting steps with UPnP as it seems to have finally resolved the issue with my Wife and I. Not sure it will help all, but this was our issue after the patch. Even though we had UPnP enabled, one of our PS4's weren't set to have a statically assigned IP address, never saw a need for it, dymanic -WAS- fine with UPnP for the game in past versions. So we set a static IP to my PS4, rebooted our systems, tried, and were able to join each other. I rebooted my machine (usually the kiss of death on past "fixes"), was still able to join each other. Final test was last night, a day after the fix, probably a fluke the night before, were able to join each other's games once again. I'll update if it breaks again, but it seems to be a pretty solid fix for us at the moment. To those that read this and need walk-throughs, I can only give examples on a Ubiquiti router.