I am not sure…this is such a hard issue as I can’t re-create the issue. But I did just get this message from my tech folks. Trying to reach some users to see if that has resolved the issue
—> After further inspection we have determined that the caching issue was happening only on the non-www page, whereas everything was working just fine on https://www.site.com. This might be a bug in W3, and as a solution we have set up your web server to redirect all non-www requests to www, so that if someone visits https://site.com will be redirected to https://www.site.com. We believe that this solution has fixed your issue, but if you have any further reports please let us know (just make sure they thoroughly delete their cache before reporting to us).