Okay, time for my walk of shame 
3 years!
My last episode before hiatus was Aug 14, 2018, and I came back Aug 03, 2021. Tbh I basically just quit and at some point I didn't think of returning.
Before that long break, I had some shorter ones, 1-2 weeks long hiatuses, but not very ofter (I used to upload one page three times a week so I could quite easily keep up with drawing if nothing irl happened).
That's for 6,75. I also have TMIC which I put on a hiatus at the same time, but haven't returned to drawing it, so the hiatus is even longer.