Come on, is it so hard to you to read more about what you are writing on?
For example, that C2-R4 was a mix of droid parts, including from the R2 series - AND - upon that, is easy to understand that C2-B5 is some kind of “evolution”.
The same goes for the “R4-P17 that’s not a R4". Yes, it is a R4, but the Jedis…