They don't "eventually" delete your data, the second the trial is over they delete the instance completely (but it still shows up in your control panel). Trying to switch to a paid subscription won't restore it and their support team can't help either.

I got burned by this, I let a trial lapse with a VM that I would have preferred not been nuked, it's totally my fault but from a customer service/goodwill perspective you'd think they would just disable access for a period of time to give you the chance to re-up.