Don't think it can. Who determines time?

Are you saying the timelock will influence the action to a specified npud Or are you saying A message to a specified npub can have a timelock?

Is there a difference in result from scheduling via shipyard?

If you encrypt the message such that it can only be decrypted by a threshold of a group of people, and you tell that group not to decrypt it until a specific time, you could achieve similar behavior. Perhaps a Fedimint module could be written to do this.

I can imagine a scenario where something like this could be approximated through DLCs on-chain 🤔

https://image.nostr.build/274690ccb82cd2c603c22cf9e71519b9e13188ed93f60e2e1a2774ebb81c201e.jpg