/Locate cannot find a stronghold and Eyes of Ender lead to invalid changing locations

Seed is 1173302408,

Originally started a survival world a few (pre) versions ago, used Eyes of Ender to locate stronghold in Pre6, was unable to locate a spawned end portal room, searched again in Pre 7 and Eyes of Ender instead lead to an invalid location. Recreated the world twice (in pre7) and in both instances /locate could never locate a Stronghold, and the eyes of Ender would lead to different locations that did not seem to contain a stronghold at all.