Vinyl siding junction at windows' built in J channels

[Arky217]

I have decided to hang vinyl siding directly on the Zip panel sheathing as recommended by the Zip manufacturer.

The nailing fins of my vinyl windows are flashed directly to the Zip sheathing.
The windows have built in 'J' channels that are 3/4" wide and 5/8" deep.

I can't seem to visualize what would keep water, when it runs down the windows' built in vertical 'J' channels, from going behind the siding when it reaches the bottom corners of the windows.

Not that it should be too big of a deal since any water would then just drain down the membrane surface of the Zip panel, but I would prefer that all the water remain on the outside of the siding.

Is there any way to manipulate the siding at the bottom corners of the windows so that no water will divert behind the siding at this point?

Thanks,
Arky