When the Love shack came out, it was a separate download rather than an update to the original game. So at that time I had two versions of Castle Story on my device simultaneously and could play either the normal, or the pink (love shack) version. After a few months the pink version was no longer supported and you were forced to move back to the normal, which did keep your buildings from the pink version. However my understanding (which may be incomplete or incorrect-if anyone knows?) is the love shack storyline/code was never in our current, non-pink, castle story. So it would have to be entirely recreated if it were to happen again. And instead that time is put into making new content accessible to everyone.
However I do think the love shack is one of the better things in the game and I would miss it sorely were it not to be there.