The good news is even though I’m not familiar with just host, you do have a current LE cert and LE should work well with cPanel. So, maybe a quick chat with the folks at just host will clear up how you can get that renewed automatically.
So as it turns out the autoSSL from cPanel was working fine. That is a great tool! It is a bit concerning that it was just rolled out automatically and nobody was really told… but the end result is a good thing.
My problem, as pointed out by the whynopadlock link, was that some of the images were still linked as http not https and I got a mixed content error. This was due to my wordpress theme and a quick google search pointed me towards a find and replace tool (better search replace) with which i searched all my wp tables for http://mech-lock and replaced it with https://mech-lock. I also added a 301 redirect to my .htaccess file to permanently redirect all http requests to https.
Everything seems to be working now! Thanks for the help.