@chyjinx I know that for zap2xml that in the case of overlapping channel # like 12.1 in your case, that they ensure to give one each it’s own channel id so that both can be listed in the guide without having issues of wrong guide information showing up.
I believe that plex has an issue with the way that they’ve implemented the guide, because when i use zap2xml, they are showing the channel id as the channel name. I have a post about it, but i’m having trouble finding it since the update to the forum…it’s not as easy to find stuff as the previous layout (sigh… 
) … found it Having issues with Grid view layout
because of the issue that i had, as well as what you’re experiencing. It leads me to wonder if in the implementation of the build in guide, that they list the channel # like 12.1 in the channel id value in the xmltv file?
from what i understand “channel id” should be used to ensure uniqueness of each channel and avoid overlapping channel issues in EPG, and “display name” should be used to display the channel number or channel name (ex: 12.1, CHEXDT).
Hope that help… and mostly hope they fix it soon.
