15thc perception on swallowtail merlons?

[R. Sale]

The link I sent will magnify somewhat.  It's clear the paint is worn off, but the colors are still pretty well in place. There are the greenish sides to the merlons, esp. on the left and center, and there is clearly another color, appropriate to the background, that sits in the center of the swallowtails. There is damage, but have the colors been moved? Not as I see it.

Admittedly it is 'out of place',  but not an impossibility.