super quick question about reading pcb diagram

[mtdelcon]

Hey, on my last build, i made a stupid mistake because i thought i new an answer, so i'm asking a really basic question here to avoid the same type of mistake. 
What do i do with C21 in this build (andromeda from Aion fx)?   I'm only asking because there are 3 holes for the capacitor.  Do i just leave the left-most hole empty?  If so, any reason why it would be there (expect maybe just an error in the board)?  Usually if there is something funky, the build notes explain, but there's nothing about C21. 
Thanks!

[MikeA]

C21 was a 3.3 uF in the original ODR-1, this BOM shows the 3.3 uF but the schematic shows a 1 uF which is fine.  The extra hole allows you to use a 1uF or 3.3 uF electrolytic cap (rightmost holes with polarity marked) or a larger, non-polarized 1 uF film cap (two outside holes.)  You may also be able to find a 3.3 uF film cap, if you prefer.   

[mtdelcon]

got it.  great explanation.  very clear.  Thanks!!