Back-End Error Messages with AcyMailing Field

Issue below looks like a harmless error warning - but just wanted to check it's not anything serious:

BACKGROUND:

I used to have AcyMailing 5 on my site. After installing the new version of EasySocial and seeing in the changelog that it now supported AcyMailing 6, I upgraded to AcyMailing 6.

ISSUE:

No problems at the user front-end, but when I edit a user profile back-end, just above the AcyMailing field I get:

Warning: count(): Parameter must be an array or an object that implements Countable in /home/thvmnzgr/public_html/media/com_easysocial/apps/fields/user/acymailing/adapters/acym.php on line 155



Warning: array_intersect(): Argument #2 is not an array in /home/thvmnzgr/public_html/media/com_easysocial/apps/fields/user/acymailing/adapters/acym.php on line 158

As soon as I save the user profile back-end these messages go away, and don't return when I edit the profile again.

I'm guessing I can safely ignore them, but just checking with you to be sure!