First off, sounds like you are talking about WLP001 (White Labs), not WY001 (Wyeast). Just trying to get a hand on what strain you are talking about.
Yeast doesn't really "curdle", it does flocculate (clump together). WLP001 doesn't flocculate very well usually. B ut it would not be uncommon for it to show characteristics of flocculation. WLP002 is very flocculative and often looks like this.