Okay, I see. I’ve been reviewing various ERC proposals, including ERC-5007, which introduces a time expiration that can be used as an expiration mechanism for NFTs, but I found it to be overly generalized and unclear, particularly when applied to specific use cases like SBT. However, I am still exploring ways to expand the expirable mechanism to make it work seamlessly for both ERC-721 tokens (NFTs) and SBTs