This is a recent problem- getting drips on the build platform and top of parts, that are coming out fully cured. How is that possible?
If your printer stays close to the window, if there is direct sunlight and if after printing you leave the part for long inside, parasitic light can penetrate partially through the protective cover and cure the resin. The drips are normal - when the platform is dipped into the resin and lifted up drips will normally form on bottom side of the platform and the detail, the problem is that there is parasitic curing light.
Personally I hold my Form3 inside a cabinet (60x60x180 wardrobe from IKEA) with closing door, on top of the cabinet I installed air extraction. To get constant weak air extraction I added in serial to the power line of the fan a capacitor 330nF/600V - this makes the fan to rotate, but on lower speed and completely silently. In the room where is located Form3 there is absolutely no smell of resin.
I got similar problem when initially I cleaned the resin in IPA under the window, forgetting the part for 2-3 minutes under the sun cures the drips
Shake the resin cart / if there is resin in the tray pre-print give it a good mix with a silicone style spatula.
also, maybe try to wipe down your cleaning platform after every print with ipa. Notably, if it has been idle for a few days, and used but not wiped down.
Resin and tray hygiene is also important as orientation.
Thanks for the replies. My build platform is pristine. Tried covering the machine with a towel in case there is light leakage, but the print I ran yesterday / last night still has cured drips on the tray and the top of the part.