"Set" after Wednesday 27Sep2023 use "dot-and-dab" to bond in reiforcement/backing and patch where vacated previous light position. Given had to make smaller holes for new low-energy ceiling spot-lights.
Later afternoon Thursday 28Sep2023 - pics to follow - another "done"
when filled/smoothed with filler ("Tetrion")
(okay; needs sanding, but done that before on plenty of other local repairs)
(R. Smith, 30Sep2023)