Can new markets be added or removed from the AvailableMarkets list, or is it sufficient to fetch the list only once?

If an available market is added to the list, will it be visible only after cache TTL expiration?

The AvailableMarkets list can change dynamically and is actually expected to for most matches. For example, CS2 player markets are usually added only some time before the match starts, or some markets/market lines can be limited at a later time. It is expected that you do a periodic pull of the list, for example, every hour. The AvailableMarkets list is to be used with the market states from the Odds Feed. So, you learn of the market being available within BetBuilder from AvailableMarkets, and the market status changes according to the odds feed. The markets on the endpoint are updated in a few seconds after the change is effected in the system. There is no waiting for the cache to expire.