In a token ecosystem, how do you guarantee that tokens will be issued at a future point in time to long-term or short term members of your community?
It is as everywhere else: You can only be sure of those things that you yourself understand and know them for facts. In your scenario, this would mean that you have some form of a guaranteed outcome, e.g. a contract that will be executed on a specific date, that can't be tampered with. In order to be certain though, you need to
know and understand all variables, not only in the contract but also everything that is part of the issuing of the tokens. As this is highly unlikely, there is no guarantee.