PROPOSAL FOR A NEW NAME/ADDRESS PARADIGM FOR THE INTERNET
This sort of idea has been proposed. In essence, the NIC would inform the customer that they don't own their address. Efforts to do so by individual providers have been legally challenged.
A complete Internet address is of the form <provider-part>.<customer-part>. If the customer decides to obtain services from a different provider, the customer shall adopt addresses using the <provider-part> of the desired provider. It shall be possible for a customer host to be multi-homed to two addresses with different <provider-parts>, either temporarily or permanently.
You don't need a second set of addresses to have a backup provider and you don't want them. If your primary provider loses connectivity to you, the DNS mapping is still to the same set of numbers, it just gets routed a different way. A second set of numbers doesn't help.
name. A server will respond with a Name-to-Address Reply (NARP) packet containing the Internet address of that host.
Acronym overload: NARP is NBMA Address Resolution Protocol. NBMA is Non-Broadcast Multiple Access. The mechanisms you describe for acquiring and disposing of address mappings differ from DHCP (Dynamic Host Configuration Protocol). The cutover can be executed by configuring the hosts with aliases (two sets of addresses for their interfaces) changing the DNS mappings while both addresses are available and then quitely removing the first set of addresses. (Except I don't think DHCP can do aliases). Nice ideas. Needs a few more margaritas. ;-) Curtis