[SOLVED] sorry, it was an unrelated routing error. 
I posted this under the HA app because I thought it was an app problem ( Android App stopped connecting (vpn tunnel) - Mobile Apps / Home Assistant Companion for Android - Home Assistant Community).
However, I think now that it may be a new configuration setting on the HA machine that is filtering traffic outside the same subnet.
I can connect through any machines 192.168.x.x, or from the HA app on the same subnet, but not through WG on a 10.253.x.x address. Silent fail / timeout.
How do I debug this? Where in HA can I get it to show me where the packet is dropped? I used tcpdump on the wireguard machine to see that packets were landing on the HA machine (no response received). On HA even with full debug, nothing shows up in the logs. I don’t have tcpdump on HA :(.
Any thoughts on how one would dig into this? Thanks