Hi dzham,
thanks for feedback, as crypto is push, the server needs to push the tokens at the right time. Maybe I can make it more clear with the following description:
Usecase: As a user I want to transfer tokens form a certain account ACC1 to another account ACC2 every month automatically.
Sample: I want to send 800 US$ every month to my land lord. I will create a XLM- Account with 9600 US$ for the next 12 month. I will presign 12 transactions with according timebounds. The server will submit the transactions every month.
If there is not enough money on the account the transaction fails. Then the landlord will contact me and ask what happened, as it would be with a normal bank account.
Special Case: If you want to make sure there is enough money on the account, we could create a escrow account, sign all transactions with the escrow key and then remove the user key from the signers. This means the user has no access any more to this account.
We also can have a chat if you like, email me at contact(at)stellarkitty.com