I don't know if this will be helpful for some players but I did a little experiment to see if I get banned.
I played for 2+ weeks on a new account with this mod. Spammed brilliant bargains to collect thousands of pages and books. Spammed energy purchases and time skips using the currency hack. Progressed to year 6 in 2 weeks. Pretty much played with reckless abandon, so if JC had a system to recognize modders without other players reporting they certainly should have banned me.
During the latest FM (ended yesterday), there were super obvious modders in the group I was in (I dont really participate in pvp events but I wanted to test this out). [For some information, I was banned a couple months ago during a house pride event the first place player was clearly cheating in although I wasn't modding at the time.] Full marks has ended and I have not been banned.
In all, it's pretty clear that you can only get banned during or right after pvp events where players can report each other (either for offensive names or suspected cheating). So if you are worried about being banned I suggest not logging in during any House Pride or Full Marks events (check the subreddit or discord for dates and times of these), or if you do log in to keep any multipliers or log in stamps, to not click on the event tiles (since a player is placed into a group based on the first time they open the task tiles for Full Marks).
Anyway, hope this was helpful for anyone worried about being banned.
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