Has anyone else experienced this?

When I SD on the iPad on 1:500000 without zooming in / out using the pinch functionality all airfield are present and correct. The same is true if if then zoom in or out using the + / - on the bottom left of the screen.

However, if I zoom in or out using by pinching the map when I loose smaller airfields, even only when zooming out to 1:505000. If I pinch and zoom back in to 1:500000 the airfields do not reappear. If I pinch and zoom to 1:495000 the airfields reappear, though go again if I pinch and zoom back to 1:5000000. If I press the + / - at any point and zoom back to 1:500000 they airfields are there.

Seem like maybe a bug with the pinch zoom?

I was looking at airfields around Wickenby.

Thanks