Your comments

I don't have anything to to with Heb Cal development, I'm only a simple user who came across your question. 

a. I think you should add what year.

b. If you are referring to Nov 30. 2024, Parshat תולדות, I don't understand your question.

"Mevarchim" is שבת before Rosh Chodesh (excusing the shabbat before Rosh Hashana).

"Machar Chodesh" is the Haftara that is read if Rosh Chodesh is on Sunday [unless Shabbat is also Rosh Chodesh].

On Shabbatot that the Haftara is "Machar Chodesh" you also add Bircat Mevarchim therefore it is "Mevarchim" as it is before Rosh Chodesh and the answer to your question is a simple "no". (I would add that Rosh Hashana will never be on a Sunday, so you can't have מחר חודש Haftara on the last Shabbat of Elul]),