Yes. GMT is UTC (meaning GMT is +0 and synchronized with UTC), therefore if you have to work out what time it is in other time zones, you use UTC. Your application shows the time in your time zone (unless otherwise specified). Responses will also be shown in your time zone.
Can’t review code if you don’t know how to. Are we meant to throw the source into AI and go, “hey is this safe”? While it may work, the time and effort sometimes isn’t. It’s literally being stuck between a rock and a hard place, so-to-speak. And before anyone says, “well, you should learn code”, I hear you. All due respect to those that can, I’m not taking the time because I don’t have time. I’m surviving from high gas prices, high grocery prices, higher bills (with for-profit companies reporting their best ever profits YOY), and keeping afloat. “Ain’t nobody got time fo dat.”
I, too, run an always on VPN from my mobile devices. I can still access my home network with pihole and DNS entries to my services. It’s not that difficult. I agree though, mTLS is a good option.