The thing is, as a citizen group, you have to set up a separate bank account. You can't use foreign money at all. The money would have to go into that separate bank account. Then, if it is used, the contributors have to be disclosed, even if the money came in before June 30. I'm quite sure citizen groups that want to go through this process will be setting up a bank account before June 30. They'll likely be appealing throughout the whole year leading up to an election year.
If a snap election is called, I don't know where they're going to get funding from. They can transfer from their bank account themselves, and I'm sure they'll send out an appeal right away to get some funds in. It all will be limited, however, based on how much money they have in an account that's not foreign money, that is not dedicated to other programs, and that can be shifted into an account specifically for the partisan activities.