[BLOCKING] Riding position offset does not function after the first "seat."

Partner Rank: 2

Verification builds: 1.6.015, 1.7.0.3, 1.8, 1.9.0.0, 1.16.0

Summary: The specified offsets for seats of a rideable entity seem to be ignored for all except for the first one. All other seats after the initial one have the entity riding at [0,0,0] relative to the entity's origin.

Use Case: The intention is to have 8 seats on this horse, each one stacked on top of the other by 1.7 blocks.

Repro Steps:

1. Download the provided behavior pack and equip it on a new world.

2. /summon horse

3. Mount the horse.

4. Repeat 7 times: /summon sheep

Observed Results: The player is positioned correctly but the sheep are all center on the origin of the horse.

Expected Results: Each sheep is 1.7 blocks above the previous one.

Screenshots/Videos attached: Yes

Notes: This has been tested with multiple players, as well as other entities.