The center to flange measurement is the least critical of the measurements.
ERD measurements affect spoke length on a 2:1 (diameter to radius) ratio, ie. +2mm ERD means +1mm spoke length
Flange diameter affect length -2:1 for a radial pattern, (-2mm dia. means +1mm spoke length), and not at all with a true tangent, ie. 4x 36h, or 3x 28h, and to varying degrees for other patterns.
Center to flange affects length on a 10:1 ratio. a 1mm difference changes the spoke length by 0.1mm
The exact ratios vary slightly within the general bands I described, but the concept holds. I offer this to spare folks the effort of agonizing over details that don't mean anything in the real world. For example a 2mm difference in CTF changes the spoke length by 0.2mm which doesn't factor when you're going to round to 1mm increments anyway.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.