RainbowAstro had added the ability to get and set the UTC Offset and the Local Date and Time back in a mount firmware update at the end of January, 2020.
I notice that the ASIAIR v1.4.4 Beta (firmware 5.45) now supports it. You no longer see UTC Offset of 0 in the Mount Info of the Telescope Settings window in the ASIAIR app.
Since neither the RainbowAstro (Korean) mount nor the ASIAIR understands the concept of Daylight Saving Time, what you will see is a representation of the local Winter time in the Mount Info window.
If your locale is currently on Daylight Saving Time, what you will see is the UTC Offset that is the Standard time's UTC Offset (i.e., for USA Pacific Time Zone, UTC Offset will read UTC-8 for Pacific Standard Time), and the Local Time readout in the ASIAIR Mount Info appears to read one hour ahead (e.g., 11 pm instead of the actual 10pm on the wall clock).
There has been no clear skies here in the Pacific Northwest (and won't be for at least another month) so I checked it out using my Mount Simulator (http://www.w7ay.net/site/Applications/MountSim/). The internal ASIAIR representation of time in ASIAIR v1.4.4 Beta appears to be OK. Objects reaches the Meridian flip position at the right time (actually about a minute late, which I think it is intentional) when the tracking is stopped by ASIAIR and then a Meridian flip GOTO is requested by ASIAIR after a 240+ second countdown.
So, 1) make sure that you have at least the 200131 firmware on your mount and 2) check to make sure that you have set the UTC Offset in the handset to the UTC Offset for your locale in Winter. That way, your handset will agree with ASIAIR.
By the way, if you are not already aware, once the mount has been correctly set up, you no longer need the RainbowAstro Hubo-i hand controller. You can leave the hand controller off completely in storage, and instead depend on ASIAIR on your tablet to feed the mount the correct time (the GPS unit of the RST-135 is in the hand controller).
I believe there could be a bug, which I have already mentioned to ZWO, that after the Meridian flipping GOTO command, the ASIAIR does not send an additional command to the mount to make it resume tracking. Since I do not use the auto Meridian flip feature, it does not bother me, but those of you who depend on completely automated image capture might keep that in mind -- check to make sure your mount resumes tracking after the Meridian flip. ZWO has an RST-150h that they can test with, so they should be able to test out the tracking resumption.
Clear skies,
Chen