Well, we don't really 100% have confirmation that there is a bug, so that's the first thing: isolate what's happening, and whether it's tvheadend or not.
What's your EPG source, and is that in local time or UTC?
I presume your system clock and timezone are correct?
And what's the setting on @Configuration -> DVB Inputs -> Networks -> Edit... EIT local time@? That should be
set if your EPG sources is using local time, and
cleared if it's using UTC.
