I don't think an index add will provide the huge opportunity to sell that you think it will, my 2 cents at least.
Personally, it will be difficult to sell because all my shares are in a taxable account with a low-cost basis, and I am in my prime earning years. It would have to be some combination of serious multiple expansion, a return to the dark ages of Fairfax that were checkered by poor capital allocation decisions, and/or a generational buying opportunity in...something else.
Biggest benefit from a December 2024 index add would be that the Fairfax 2025 thread won't be filled with posts speculating about index inclusion.