Groovy.lang errors in log related to LinkToHub/HubLink

Howdy,

I've got 2 hubs. I use HubLink & LinkToHub between them. I just noticed that my 'slave' hub has a few errors in the logs. See screenshot:

I'm not experiencing any perceivable issue with performance. I'm also not sure how I can resolve the issue, or if it might cause problems down the road.

If there is any additional info I can share to help troubleshoot, or pointers so I can self-resolve the issue, please let me know. Thank you!

CC @bobbyD