Bambu Slicer won't bridge painted surfaces, instead creates overhangs

I’m trying to paint a negative feature on the bottom of my models,
letters\numbers etc because I need text on both sides…
should be no issue but instead it turns what should be an easy bridge into a pure overhang…

to demonstrate, take a standard 20mm xyz cube… flip it upside down, and paint the Z



if I remove the painted surface it bridges the small gap just like anything else no problems