"Safari enabled" expiration not disclosed

I just purchased a Safari-enabled book (Information Dashboard Design) last week and it's being removed from Safari on Monday at O'Reilly's request. The book is only two years old, it's current on Amazon, and it's on shelves in numerous bookstores. I feel the claim on the book ("Free 45-day online edition") is deceptive.

I understand that every book can't be archived on Safari forever, but at a minimum the full-page Safari promo on the inside back cover should display an expiration date, so people know the "free 45-day" offer has passed. Anything less is deceptive advertising.