Thank god someone finally built this, I've been kicking around this for forever in my head (glue together some STT library and logic to adjust subtitle offsets) but I never had the time.

Really I wish Plex would just build this in, it's right up their alley. Movies aren't terrible since you can adjust the offset once (still a huge PITA and I feel like a toddler making an "L" with my hands to tell right from left when it comes to knowing "Do I need to increase or decrease the offset to fix this?", "Ok, I saw the subs before I heard it so I need to increase the offset", etc). TV shows are a whole other cluster. To be fair 80%+ of the time I have no issues with subs on my TV shows but if it's off then you can plan on readjusting after almost every commercial break.

I used to watch Letterkenny and I needed subs for that show to keep up but the only ones I could find were off and after each commercial I needed to adjust them by over 5 seconds which, at 50ms intervals, is a massive PITA.