I want to set up a multisig that requires fewer signatures as time goes by.
Let T be some time in the future (e.g. a year from now).
Before T, 2/3 signatures are required to unlock the UTXO (send coins). After T, 1/3 signatures is required to unlock the UTXO.
The idea is to provide a recovery mechanism in case I lose 2 out of 3 keys. If I do not lose 2 keys, then my multisig would be just as secure as a regular 2/3 as long as I move the coins before T. If I lose 2 keys, then I have a recovery mechanism as long as I still have 1 key and none of the 3 keys were leaked.
Is this possible in Bitcoin, and if so, how? Is there a user-friendly tool that lets us do this? Thanks in advance!