Hi Cezz,
According to the three screenshots you provided, it indicates that you have experienced a service update for your SharePoint Online service, not a service upgrade for your entire Office 365.
I suggest you add "/_vti_pvt/service.cnf" to the end URL of your SharePoint site, like <tenantdomain>.sharepoint.com/_vti_pvt/service.cnf, to check the detailed SharePoint version.
If your SharePoint version is like 15.x.x.x or even 16.x.x.x, then it exactly indicates that only your SharePoint Online is updated.
Thanks,
Cherry Wang