"Switch" button missing "Use Facebook as Page"

About 2 months ago the "Switch" button disappeared from the "Use Facebook as
Page" feature for 2 out of 5 of the pages I'm Admin of.

Also the corresponding "Use Facebook as [Page Name]" button is missing when I
view the page.

I can still manually share a link as a page that has lost the switch option
via the "https://www.facebook.com/sharer/sharer.php?u=www.google.com&src=sp"
link...

I've logged multiple bug reports via the Facebook Help center and have had no response.

I've also logged a Facebook Developers Bug
[You must be registered and logged in to see this link.]
no action or help as been supplied from there...

Please help as I need to be able to switch to our pages.

Both of the pages are associated via Open Graph to the corresponding webpage home pages.



Cheers Knud