The callback_address can be tz1...%getProofsCallback.
The smartpy code would then look like:
c = sp.contract(TGetProofsResponsePayload, callback_address).open_some()
The CONTRACT instruction CONTRACT %name t has annotation as you can see and those cannot be dynamic.
To get the address with entry_point information you can do:
# when building the callback
No, there is no such opcode. You can however add functionality to you contract that puts it in a final state, sends any funds in it to a designated heir contract, and then rejects all incoming transactions.
This functionality is not available in Taquito, however, if you need that kind of information in your dapp, you can use an indexer, for example, with the TzKT API, you can retrieve a list of smart contracts.
The main benefit of such an instruction would be an automatic transfer of existing resources and tokens to a heir contract. However, the current Tezos token contracts do not seem to support "inheritance".
It also would allow to save space for the contract storage, but this is secondary issue as compared to the safety of resources.
Without such a ...