Interesting as my experience with processing quite a bit of 80S and Superpan 200 is the opposite. I see a lot of curl lengthwise with 120, so much so that the film can still be stood on it's edge after storage under weight. Even the entire negative sleeve can be stood on it's edge. By contrast, TMY2 120 for instance dries amazingly flat. This is with a final rinse in Photo Flo. I would be curious if you are using a different wetting agent that might be giving flatter drying. Developer is either HC-110 or Rodinal. Adox CHS 100 II also curls a bit but not as severe as 80S and Superpan 200 in my experience.
80S is a film I have shot a lot of lately, purchased from both B&H and Argentix. Two different batches (one older and one newer with the different backing paper). Same experience with both. Beautiful film imo but the curl and, to a greater extent, the dirty film/ emulsion issues and or quality control (seen when scanned at hi res) are deal breakers for me.