If you waited 15 mins or so after the event and then DCed I don't see why you were banned for LTAP as this is a long time and you weren't even brought to a sit. In my opinion waiting out this time was correct and then as no-one had reported you (or so you thought) you left.
This ban seems a bit unfair to me personally and I think you could stand a chance at being unbanned.

If you waited 15 mins or so after the event and then DCed I don't see why you were banned for LTAP as this is a long time and you weren't even brought to a sit. In my opinion waiting out this time was correct and then as no-one had reported you (or so you thought) you left. This ban seems a bit unfair to me personally and I think you could stand a chance at being unbanned.