Okay, so there are flaws with this. There is first. Because it depends on whether in the future, the good guys or bad gouts see the communications first. If the bad faction of time travelers see the message first, they could come destroy the data. You could hope that the good guys see it later in the timeline and undo that by rescuing you with your data but there is still a circle effect going on. The bad guys can still counter the good guys and vice versa. An endless undoing/redoing cycle.
You place X amount of messages, but it is not specified how many enemies versus good time travelers there are. So it is impossible to know who will see one of your messages first, starting the cycle. Even getting the data to a safe place, someone in the timeline along the way can see your messages and go to a place to stop you from securing said data. It would be never ending. The idea is to let the good guys know without the bad guys if you go that route. If you rigged the messages cryptically and they ended up asking a question that only the good time travelers would know, giving them say a location to rescue you for this plan to work.
The real answer is that time travel to the past is never possible.