Persistent Hellspires after Helltide ends

I’ve discovered a bug regarding the Hellspires that appear within a Helltide.

As we all know, when activated, they create a player boundary area and begin spawning an increasing number of enemies and ramping up in ground effect dangers. This normally lasts for about two minutes or so, or until there are no players inside the boundary that was created when activated.

I activated a Hellspire yesterday in the hopes of reaching Max Threat (to call a Hellbourne) before the Helltide ended. The Hellbourne spawned before the Hellspire ended and was subsequently killed, and within seconds the Helltide also ended.

However, the Hellspire persisted. And persisted. And persisted!

Leaving the boundary did not work (at 7:25 in the linked video). Using my Town Portal to exit (7:45) to and return from (8:13) The Tree of Whispers did not terminate the Hellspire as it should have.

The video I captured is nearly 10 minutes long (longer actually, because I started recording only after I realised something was wrong), indicating the abnormal (and obviously buggy) duration of the Hellspire that should have stopped working when the Helltide ended.

https://youtu.be/0iv9Xc1dWIs