Assets can be assigned to a Location. Changes to that will be tracked in the Asset History, so you could review that information at any time.
You might be able to leverage one of the fields like Warranty Expiration or the Service Contract/Contract Expiration fields to specify a date in there. For those, there is a universal WHD setting that can email-notify you when those dates are coming up (e.g. 10 days before or 3 weeks before or whatever you'd like).
That wouldn't require using the "reservation" functions at all.
You could also define an Asset Custom Field and specify that as a Date field.. that could track the 'expiration/move' date with a more descriptive name...but you wouldn't be auto-notified when that date was coming up. (the notification only works for a few pre-defined fields)
Did you ever have any luck with this? If not this, something else?
I'm interested in tracking tapes outside of the storage vendor as well!