admin bar disappearing

Has anyone noticed that the front end isn’t holding login credentials unless you refresh the page. I log in, open the front end of the website but the admin bar is not present and my meta link will be to login and not admin. If I refresh the page, they both come back showing me as logged in. I’m seeing this on a few sites now since 4.7. I’ve tried switching off different plugins and themes but haven’t figured out a pattern/conflict yet.