Often shows are released way later than what TVDB claims. Maybe there have been cases where it’s earlier too? I have not witnessed such a case myself.
I was wondering if a tag could be added per series for delaying/fastening the runtime on the calendar by X hours and Y mins. For example, tag:
onehour would add one hour to the run time of each episode in that series.
So it would be run time from TVDB + an offset.
Sonarr already works perfectly for me and this would just be a small tweak that would make the airtime more accurate, as I use the Sonarr calendar a lot.