I understand that there is a similar thread going on right now about this topic as included below. Decided to post this question as I noticed that It has been awhile since I saw any further progress regarding this issue.
I am currently running a multisite with 100+ sub-sites and experienced this problem after performing the latest plugin update from 188.8.131.52 to 184.108.40.206 which affected the functionality of the Single Sign On feature. Disabling SSO enabled the sites to operate normally but I will have to login separately to each of the sub-sites.
I have attempted a manual roll back by uninstalling the current plugin before uploading and activating the previous version of this plugin. The sites manage to have their SSO working again but there are 2 more problems now. The first problem is the sub-sites that were logged into now cannot be logged out and will keep returning to the page before I clicked logout. The second problem is due to the SSO cookies not being handled properly, an essential plugin that my client uses, Jetpack security is blocking access to the other sub-sites on the multisite network if too many sites are accessed concurrently.
I would like to know when and if there will be a fix for this plugin as it is currently used in a large commercial project for my client. The project cannot be closed until this problem is resolved as the functionality of this plugin is a very essential part of the project.
Really appreciate a reply on this issue soon. Thank you.