Custom Theme and unpredictable Suite Bar design behavior

[ErnoEronen]

The suite bar design seems to change unexpectedly and I'm not able to predict how its going to look from tenant to tenant, service to service and from time to time. As a design-minded person I would like to fully understand, how the suite bar design works, before presenting design options to clients.

So sometimes the app launcher shows the accent color (with square grid icon) and sometimes it shows the nav bar background color (with circular grid icon). 

Here is a screenshot from a tenant that first had nav bar colored app launcher (2) last week and today, after a page refresh had an accent color launcher (1). So the other screencap is before a page refresh from the same tenant, the (2) changed to the accent color version after page refresh. Sharepoint seems to be the most undecided, but I've seen this behavior in office.com, admin center etc. 

Is there logic, is the other one a new design or what? 

[#2]

@ErnoEronen Replying to my self, that that thanks to a colleague I found this post https://techcommunity.microsoft.com/t5/Microsoft-OneDrive-Blog/OneDrive-Message-Center-Updates-Janua... which suggests that this is a design change rolling out, which is just behaving erratically for me at the moment. Now I know where to aim and just wish that the new design will work more reliably in the future. The tenant pictured changed to the new design again today :)