Time Syncronization for offline gateway relays

Hi, I’ve been testing relay gateways using RAK2287 concentrators. It worked well in the lab but once I deployed one in the field I neglected that because i don’t have a concentrator with a GPS module and its not connected to the internet, the time is drifting. At the moment this seem to be only affecting the last seen value in the gateway mesh page as it gives this warning:

chirpstack::uplink::mesh: Time is less than last seen timestamp, ignoring stats

Is there any way for the border gateway to either ignore the relay’s timestamps or send some sort of time synchronization packet?

I could upgrade the concentrator include GPS but then you have to rely on that signal which may not be the best especially in inside spaces.