Burr seasoning is really somewhat annoying.
But if the numbers that Lance presented recently are to be believed, then it will make an impact on overall extraction quality and grind uniformity, after hitting a certain amount of beans running through the burrs.
Starting at 5kgs for the first big jump.
More will continue to improve, but with diminishing effects.
Especially for flat burr grinders, for conical burrs it doesn't seem to have that much of an effect overall.
So .. aiming at the 5kg mark for my DF64 espresso grinder (which already had a few kg of coffee already, so I am not _that_ far away).
I don't think I will try to season my Fellow Ode, tho. That would require far too much coffee getting more or less wasted (as you really don't want to run your favorite beans through) and the effects aren't as strong compared to an espresso grind.