If you have a Gateway of any type and a Fritzbox mesh network (some other mesh networks give problems too) the Gateway may freeze every couple of hours. There were about 6 users that reported this.
We are working on a fix. If possible stay on firmware 3.5.1 or older.
If you experience the issue, please add a comment on the Github repository:
https://github.com/emsesp/EMS-ESP32/issues/1321
Edit 1 November 2023: When using 3.6.3-dev4 or later you can set the WiFi to a fixed BSSID so that it does not move to another WiFi mesh point.
Most users report dev4 gives them a stable system again.