If I teleport a armor stand to a certain direction (Like /tp @e[type=ArmorStand,c=1] ~0.1 ~ ~ 180 0) It sometimes looks into the wrong direction.

Here's a video: https://youtu.be/ZktELeeIpqI

Also, that "message me on Twitter" thing is'nt true, I decided to upload a schematic. If you've loaded it you have to add some scoreboards:
/scoreboard objectives add legs dummy
/scoreboard objectives add speed dummy
/scoreboard objectives add direction dummy

Then just place A Standing Banner (Color is not important) At Y=1 and a wool on top (green, yellow or orange) like you can see it at the beginning of the video. Last step is to place a armor Stand on the wool. Then it'll walk and you can (hopefully) see the bug.

Thanks for fixing, puchm