toolbar positioned at top of view displays correctly except on retina 4" on which it is positioned down the screen

toolbar positioned at top of view displays correctly except on retina 4"
on which it is positioned down the screen

This is a 320 x 460 view controller containing a toolbar positioned 160 x
22. All struts are set for the toolbar except the top one.
Below this on the screen is a view (called child view container) that
fills the rest of the screen (size 320 x 416, position 160 x 252).
I am not using auto layout.
This view controller displays correctly on all iphone simulators except on
the retina 4" running iOS 6. On this simulator, the toolbar is shoved some
way down the screen behind child view container.
The parent view has all springs and struts turned on.
I would have thought that the lower strut being set for the toolbar would
ensure that it remains at the top of the screen. There is no code within
the app which amends the shape and size of the toolbar. the contents of
child container view are set programmatically.
Here is a screenshot of a correctly displayed 3.5" retina display:

This is a screenshot of the 4" retina display:

If the start exercise button is tapped, the viewed screen changes to
another one, and while that is animating, I can see the toolbar appear a
the level of the first line of text (The model is like a patient...).
How do I change the toolbar settings to ensure that it remains right at
the top of the screen, on whatever iPhone the app is used on?