I created a new application using the Split View-based Application template.
I then added an Action Button to the rootViewController navigation controller called actionButton.
When the button is pressed, I display an ActionSheet like this:
UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:nil
delegate:self cancelButtonTitle:nil destructiveButtonTitle:nil
otherButtonTitles:@"Admin Functions", @"Refresh Data", nil];
[actionSheet showFromBarButtonItem:actionButton animated:YES];
[actionSheet release];
After I press the button when in landscape mode it displays the action sheet in a popover which is pointing to the button (as I expected it to):

However, in Portrait mode it looks completely different and the menu comes up from the bottom of the rootViewController popover just like it does on the iPhone:

My question is, how do I make the ActionSheet appear at the top while in portrait mode, just like it does when in landscape mode?
Since this is a “utility menu”, it isn’t really tied directly to the data being displayed so it shouldn’t be part of the popover.
This behaviour is by design, if it were a popover in portrait mode you would then have 2 levels of popover.
This is technically possible by implementing your own version of UIPopover or using one someone has already written (WEPopover).
However, this is a poor design choice. You say that the functions aren’t related to the data, however one is ‘refresh data’. I would replace the action button with a refresh icon such as the one Apple uses in ‘Find my Friends’:
The other, ‘Admin Functions’, if not directly related to the data in the list, perhaps needs a new home, maybe with the main view of your app? It’s hard to say where is best to put it without knowing more about the structure.