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Loving this crazy thing need some suggestions and learning

I would like to know how you are storing the values of the offsets, are you doing it in storage or anyother thing? If there is anything would love to know + does it stay for any amount of days or is there any limit and then it gets deleted from the storage.
Another thing i am wondering how do you keep track of it? do you keep a map like id -> offset value or something.
Would love to learn from you please reply me