Been working great on RC4-4 for 100+ hours of print time so far. Made the mistake of updating to RC4-6 80% through a long print run because it was available... one of these days I will learn. Getting an error after not changing any config files at all - just updating that pin PA9 is used multiple times in config.
I tried commenting the PA9 line out in my printer.cfg - seems to cause an error where it will boot up and crash. PA9 either maps to A) the part cooling fan on my SKR Pro or B) the filament sensor switch on my EBB42g2 (although that is toolboard0:PA9)... but the error changes when I comment out the toolboard PA9 line). I tried changing around the toolboard PA9 to another pin# to see what happened and it followed the pin name around... so I think it may be that line that it's mad about... but I don't know what to do about it.