Do json exports expire?

[vikram]

We cannot absolutely guarantee that backups before 1.0 will be directly importable in future versions, but we will try our absolute best to make sure that they are. If compatibility has to break at some point, as long as you still have the backup with your encrypted private keys and still remember the password, we will provide a mechanism to import those keys.

[bitAndy]

I have basically invested as much as I can afford into Bitshares & think I'll just HODL long term. I still need to claim my vesting AGS balance but I'm sure I can do that in the future.

Until I'm confident using linux distros (I'm using windows) I would rather just delete the wallet file off my computer to be safe & have the json files on a number of usb sticks to import months down the line. But is it best practice to keep the wallet, update & export from the most recent wallet that's out or is it completely safe to import old jsons in the future... So if I export at 0.5, there would be no reason as to why that wouldn't import at say 1.5?