High Sierra limits number of accounts that can be opened.

I have been running my iMac for years with seven active accounts established (family members, emergency admin, etc). I have always been able to be logged into all seven accounts simultaneously, which I do from time to time just because). Since upgrading to macOS 10.13 High Sierra when I attempt to login to the sixth account a pop-up window opens alerting me that the maximum number of accounts able to be opened has been reached. I have to logout of one the open accounts in order to login to another. The maximum numbers appears to 5 accounts now that can be logged into simultaneously.

Not earth shattering or game stopping but I’m looking for information and or confirmation that this change is real and what the possible reasons for it might be.