Update Scanner reports: Chapter 1 has been edited so that Petunia recounts that she was ugly and Lily's potion improved her skin and curves, but no longer mentions having been fat nor losing weight thanks to the potion. As a secondary change, possibly unrelated, Prof. Verres is also more tender towards his wife, an improvement on his characterisation.

My working hypothesis is that Eliezer is going to set up some rules about what potions can do (possibly just Polyjuice and variants), which could not be reconciled with sudden weight loss.