The mode that allowed you to start a franchise mode from the current date is not available in NBA 2K21 and we got a reasoning for it according to Brian Mazique from Forbes. According to 2K since the game was completed prior to the NBA finalizing the schedule for the current season, there was no way to have it ready for launch since the entire feature is connected to the real NBA ledger. As far as adding it to the game with a patch the 2K dev said “It would be a major effort to retroactively support it on a live product with live saves and all that.” Brian reached out to a representative from 2K to get an idea of when or if the feature will be available but there’s no confirmation.