Which wallet are the unclaimed SPS held in currently? If it is a dedicated wallet, maybe we leave the unclaimed assets in there, but pass the keys and ownership to the DAO going forward (and it can be included in the DAO Treasury reports)
I understand the point of an end date is so the claiming code can be removed and cleaner code going forward. My preference would be a longer notice period rather than just a couple months. I'd think that if they can take a snapshot and post the list of eligible claims on chain, and maybe send a 0.001 hive memo with the details to the inactive wallets or the HIVE wallets where any offchain assets were sent from, that might be the cleanest record showing we tried.
Then if we have a longer "Notice Period", maybe we get some coverage over a few months about the "Airdrop ending - claim your assets now!" sort of thing.
Afterwards, if needed, the DAO could manage any residual claims manually if people could still submit a ticket if they felt they were owed SPS from the airdrop.