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Class members get their first class free, so to be sure there's a financial incentive for class members to buy a subscription, the subscription period starts the second week of class and finishes the last week of class. This exactly determines the dates of all of the subscription periods. The dates for class are determined by the PE calendar which is related to the academic calendar. Tech Squares has a handy projected dates spreadsheet. (Note: As of 2022, class members now pay a separate "class fee" rather than buying a subscription and checking in at gate — therefore, possibly we should just realign subscription periods with the start of class.)
We don't dance when MIT is closed, and prices need to reflect that. MIT is closed:
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