IERC721 Retroactive approvals: disabling approvals before time

Magicians Primordial Soup
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Upgrade to IERC721 approval system
(content-finance-contracts/src/token/erc721/IERC721RetroactiveApprovals.sol at master · sebasky-eth/content-finance-contracts · GitHub)

IERC721RetroactiveApprovals adds extra dimension to approvals: time. Every approval saves information about date, which are compared with retroactiveDate to decide its validity.

It could work in three ways:
A) Adaptation to current system
retroactiveDate cannot go to future. So if dApp call for approval, it will work as expected

B) Silent Freedom
retroactiveDate can go to future.

C) Loud Freedom
retroactiveDate can go to future. But calling approve or setApprovalForAll, if retroactiveDate is futuristic, must revert.

Gas cost
It could be minimalized in bitfield implementation of ERC721.

Supply data could contain retroactiveDate.
Token owner data could contain date for token approval.

But operator approval date need to be read during transfer, if necessary.

Code:

interface IERC721RetroactiveApprovals is IERC721 {
  event RetroactiveApproval(address indexed owner, uint256 retroactiveDate);
  
  function retroactiveDate(address owner) external view returns (uint256);
  
  function approvalDate(address owner, address operator) external view returns (uint256 date);
  function tokenApprovalDate(uint256 tokenId) external view returns (uint256 date);
  
  function disableAllApprovalsBefore(uint256 retroactiveDate) external;
  function disableAllApprovals() external;
  ///acts like: disableAllApprovalsBefore(block.timestamp + 1)
}