OP_IF <one month in the future> OP_CHECKLOCKTIMEVERIFY OP_DROP <Alice's public key> OP_CHECKSIGOP_ELSE OP_HASH160 <Hash160(x)> OP_EQUALVERIFY <Bob's public key> OP_CHECKSIGOP_ENDIF
<Alice's signature> OP_1
<Bob's signature> <x> OP_0