I run kstars/ekos/indidriver on a RPi 4B with StellarmateOS as the server. As clients I can use Mac, Win8.1 or Kubuntu as clients. I use a GPs mouse to update the client/kstars etc.
Between server and client is a time difference of exactly one hour. The server is one hour behind the local time, as the server correctly shows.
That is suspicious, ok?
I have already checked the following:
1. System time settings on server and client - ok
On client/ekos:
2. location - ok
Time and date settings -ok
DST in GPS Driver - ok
UTC difference to my local time is set correctly
One hour means there is a DST issue somewhere. The GPS driver provides UTC. I presume you connected SM App to StellarMate at least once to set the timezone? If not, then check the timezone setting in StellarMate.