photos "recently" deleted months ago 'back to life' in iCloud.com?!

Hi all,

Since the introduction of the "recently deleted" functionality, photos I'd deleted from my iPhone would sit in the recently deleted space and permanently disappear after 30 days. ...That's what I thought! Then I just recently got a new MacBook pro with Yosemite and decided to start using the iCloud Photo Library. Now all the "recently deleted" photos since the beginning of time are reappearing in iCloud.com! That means they were never permanently deleted (despite not showing up on my iPhone any longer)! Which is not only awkward but quite alarming too!.. These photos only show up in iCloud.com's recently deleted photos, but not in my iPhone/MacBook's recently deleted... What the...?!?!?

Is there an explanation for this?

Thanks