ἐφ' ὅσον αὐτοῦ ἡ ὑπόστασις τῶν χρόνων ὑπῆρχεν → as long as his store of years lasted
δύσνιπτος, δυσεξάλειπτος, δυσαπάλειπτος, δυσεξίτηλος, δυσαπότριπτος