The sill here has very little overhang and the compromised paint had left it looking like soggy mulch. After cleaning up the opening, it looks like the person who installed the window didn’t flash it properly (they just caulked the joints but didn’t integrate it with the existing WRB, which you can barely make out behind the shingle siding). Do I remove the rest of the trim and see how deeply the rot goes, or is there a reasonable way to patch the sill until I’m ready to take on projects like new window, new siding, reframing, etc.?
I think my fundamental issue is the complete lack of overhangs.