Nether portals

Entering nether portal then promptly exiting should return player to initial point of entry entry 

Steps to Reproduce:

1. Build and light nether portal at coordinates -2988,50,643 (portal A 
2. Enter portal and promptly return to overworld
3. Exiting nether to overworld will deposit you at coordinates -3625,70,721(portal B)

Observed Results:
Breaking portal B has no effect; when returning to portal a to re-enter nether, promptly exiting will result in new version of a portal in a slightly off position in same general vicinity of previous portal B

Expected Results:
Player entering portal A should return to same portal

Screenshots/Videos attached: [please attach an image or short video]

Notes: