The Bug:

Nametagged creakings despawn if they forcibly wander too far away from their heart.

Steps to Reproduce:

Follow every step top to bottom, even though I may have mistakenly messed up the step number order.

1. Create a superflat world with the Classic Flat preset.
2. Run command: 

   /fill ~3 ~55 ~3 ~-3 ~55 ~-3 diamond_block

3. Now, Run command to get to the diamond platform you just made: 

/tp ~ ~56 ~

1. Place a pale oak log on the centermost diamond block. The pale oak log has to be on its y axis.
2. Set the time to day.
3. Place a creaking heart on top of the pale oak log you just placed.
4. Now place a pale oak log on top of creaking heart you just placed.
5. Set the time to midnight.
6. Run this command: 

   /tick freeze

    

1. Use a renamed name tag on a creaking.
2. Break any blocks the creaking is on.
3. It might be helpful to show entity hitboxes using F3 + B.
4. Run command:

   /tick unfreeze

    
    

1. Watch as the creaking breaks as it gets too far from its heart. 

Expected Results:

Nametagged creakings will not despawn if they get too far from their heart.

Observed Results:

Nametagged creakings will despawn if they get too far from their heart, despite the fact their heart was not broken.

Notes:

This report does not duplicate MC-277070. The linked report talks about named creakings despawning in daylight, but this report talks about named creakings despawning when they get too far from their heart.