I would say so, Big'Uns can have a Magic Banner and SOBB can have a Magic Banner... Simple if you ask me... Or are you now saying that because it only says Big'Uns can have a magic banner at normal Orc Boyz that Savage Orc Big'Uns cant have one??
It is a different unit, they have different stats, you can have only 1 of them and they have a different unit name (ie Savage Orc Big'Uns instead of Savage Orcs)...
Different units, both can have a Magic Banner imo...
Can you please share with the class where it says all biguns can have a magic banner?
The simple answer is that it does not.
It says SOBBs can have one for a single unit. To qualify for the magic banner, the biguns are relying on the fact that they are
SOBBs. Without this status as SOBBs, they are not entitled to anything. So, by your argument that they are seperate units, biguns on boars cannot have magic banners. It's your logic that leads us to this, not mine.
But then the truth of the matter is that they are SOBBs, and therefore fall under the limit of one per army for magic banners. It's a unit upgrade. They are not in any way listed as a seperate entry in the army list.
Increased stats aside, they are still the same unit type. Or is a unit champion no longer of the troop type defined by the rest of his unit (for whatever difference this may make)?
So, in conclusion, savage orcs boar boyz can only have on magic banner, whether they take the biguns upgrade or not.