I wrote to Photobucket, complained, asked if there is ANYTHING we can do. Here is the reply:

We would love to leave them up for you to use but this decision came from
Adobe the creator of the Remix. They are doing away with this. We are
incredibly sorry and at this time you can use our slideshow feature to
somewhat recreate the Remix you have created. We are sorry for the frustration
this has caused but we have no control in this decision.

Sincerely,

Your Photobucket Support Team