With the new update comes the new realative system for teleporting entities.
There are different cases wich won't work quite good.

The first case:

When you teleport (in this case a Sheep) to an Armorstand (called teleport) are different cases with this new mechanic. First case without relative directions and second case with relative directions. The result of both cases ar the same. The Sheep gets the Rotation of the ArmorStand with both commands:

/execute @e[type=ArmorStand,name=teleport] ~ ~ ~ tp @e[type=Sheep,name=Tracer] ~ ~ ~ ~ ~

/execute @e[type=ArmorStand,name=teleport] ~ ~ ~ tp @e[type=Sheep,name=Tracer] ~ ~ ~

In one of those commands it has to behold the relative coordinates of itself. Because these two are simply doing the same. And it would be a good thing for Mapmakers

The second case:

The teleporting of a Player with thesese Relative coordinates won't functure at all. It simply does nothing. The commandBlockOutput says that the player has been teleported to the ArmorStand but nothing happens.

/execute @e[type=ArmorStand,name=teleport] ~ ~ ~ tp @a ~ ~ ~ ~ ~

/execute @e[type=ArmorStand,name=teleport] ~ ~ ~ tp @e[type=Player] ~ ~ ~

These commands doing although the same, nothing.