[asterisk-users] OT: Have unused DID's; where to warehouse?

[sean darcy]

We have a set (about 20) of DID's that we're not using. No one calls 
them, and we don't need them for outgoing.

I'd like to keep them for future use. We now pay $5/mo/DID to host them. 
Is there a way to "warehouse" them? Just put them in a bank someplace?

Thanks,

sean