Fear no degradation!
The ‘sticky’ function is what you’re looking for, and it was designed for this in mind.
For the main text, no need to use the sticky function, as you know. Simply apply M to all pages, and a special chapter-opener master to the first pages of each chapter.
Next, beneath these setting (to override them, they must be beneath), set up 2 rules.
(1) Apply your F-master to the front-matter-opener style, and check the ‘sticky’ function to make that setting stick until the next instance.
(2) Beneath (1), again select the front-matter opening style, and this time choose the front-matter-opener master page, and make sure the sticky function is unchecked.
This will cause all prelim pages to have the F master applied, and the prelims openers to have their own master page applied.
That way you can have different running heads for prelims/end-matter (e.g. Introduction on both recto and verso), and for regular chapter, say Author and Book Title or whatever.
Let me know if that works for you.