Mobile sub menus open on load

Hello, first off thanks for this great plugin. Really useful and well built.

I am however struggling to find a solution to help me force the sub menus on my mobile nav to be closed when opening the off-canvas menu. At the moment when opened on mobile or tablet all of the mega menus and flyout menus are open with the sub items on display and I would ideally like these shut and ready to be opened by the user when they are ready.

Any help greatly appreciated. ??
Dan Bell.