you can create your own M3U and just re-number the channels yourself if docker is out of your wheelhouse...my container just does all the work for you but you can certainly create the file yourself if you're more comfortable doing it that way.
example: here's the M3U portion my container spits out for remapping TV Land from 6021 to 304 (which is the directv number):
#EXTINF:0 channel-id=“6021” channel-number="304" tvg-chno=“304” tvg-id="304" tvc-guide-stationid="74134" tvg-name="TVLANDP" tvg-logo="https://tmsimg.fancybits.co/assets/s73541_ll_h3_aa.png" group-title="",TVLANDP
http://192.168.88.165:8090/devices/TVE-ATTOTT/channels/6021/stream.mpg
192.168.88.165 is my channels server. 8090 is the port number secondary channels instance i've set up for the backend, if you're only running one instance this would be 8089 for you.
the URL format would be the same for every channel, just change the device to whatever device you're using and the channel number to whatever channel you're mapping.
change the channel-id parameter to match the DVR channel number that you just put into the URL.
change the channel-number, tvg-chno and tvg-id parameters to whatever channel number you want that station to use.
change the logo to match the correct logo for the station you're loading (i.e. the DVR station logo).
as you can see there's a lot to do, which is why i wrote the code to do it for me...but you can certainly do it on your own. it'll just take some time to map a large number of channels that way.