I would agree with you, but as the player count of TF2Center and TF2 in general decreases we are no longer able to condone or allow the usage of non-rotation maps for lobby creation. We are working towards adding the rule and making a public statement. However, you still create lobbies using unheard of / "new" maps that should be tested on your own time using a steam group or discord pug system instead of using our service and taking up a lobby slot.
A couple years back it would have been perfectly fine to have a lobby with a new/unknown map, as there would be so many players that several more lobbies of the same type with active rotation maps could go up, fill, and yours would not be causing any problem. However, now with limits to how many lobbies may be active at one time, creating a lobby with a new map that most players won't want to play only causes frustration and annoyances in which players that use our service with the intention of playing active rotation maps in a competitive setting can no longer do so. Most players would not be interested in downloading a map they've never heard of and playing a map that has never seen actual competitive testing. This would drive population numbers down even more during the time your lobbies are up, as players would be uninterested in waiting an hour for your lobby to fill before they can make a new one with a more viable map option.
For now, I will remove your ban. However, do note that I will re-instate the permanent CL ban if you continue to create lobbies with non-rotation maps. TF2Center is not, and was never intended to be, a place for the testing of potential league maps. Surely there are enough people in ETF2L (EU) or ESEA (NA) that you can add or get in contact with that will gladly test out your map in a more serious setting in private rather than with our service.
Your method of using TF2Center to test these maps is also not effective in my opinion. You will fare far better by getting a group of 12 players who eagerly wish to test the map rather than having players be forced to play it because it's the only option late at night / early in the morning when not enough players are online for a second 6v6 lobby to go up. You would fare much better by getting actual mid to high level teams to do a practice run of the map, talk with top level players for suggestions/feedback as to what they think about the map without playing it, or gather interested mid-high level players and do a mixes/pug style playthrough of the map.
So in conclusion, your ban is removed. Do not make any more lobbies with maps never used in any competitive leagues. If you just can't and need to use TF2Center to test maps, then I'll gladly reinstate your ban with no appeal chance.