Disturbing and Orwellian:

Owners of Roald Dahl ebooks are having their libraries automatically updated with the new censored versions containing hundreds of changes to language

Source: Roald Dahl ebooks ‘force censored versions on readers’ despite backlash

What this means – you’ve previously purchased an e-book edition of a Roald Dahl book and have it on your e-reader. The publisher is now remotely altering that copy on your e-reader to replace it with a new, sanitized version that is not what Roald Dahl had actually written.

Basically – e-books are subject to mutation, over time.