Rabid fans hoping to get a glimpse of pop stars-turned-judges Demi Lovato and Britney Spears at the two X Factor tapings at the Fillmore Miami Beach were plum out of luck Thursday. One was set for 1 p.m., the other 5:45 p.m.; both were a wash.

For unknown reasons as of press time, producers decided to nix the live-audience feature early Thursday morning and sent an email notification out to ticket holders at 2 a.m., long after most Web surfers had gone to bed.

Participants who showed up as early as 10 a.m. were given the bad news to head back home. Others who phoned ahead to the venue were spared the hassle and humiliation: “We regret to announce that the ‘X Factor’ tapings for this afternoon have been canceled. We apologize for any inconvenience this may have caused,’’ says a recorded announcement at The Fillmore.

Rejected audience members took to the OCA http://on-camera-audiences.com/shows/The_X_Factor to voice their displeasure:

Wrote Ivet Ludena: “Very disappointed the live audience for Miami was cancelled for XFactor! Especially considering i took the day off of work for this.”

Another, Dianne Prokos, added: “I just got home after driving to Miami Beach for the recording of the Boot camp to be informed that they decided not to have a live audience. I never received any email from them and this is not right. There were people there that came from Brazil and Colorado and they were p---ed. All you Miami fans let’s not support the X Factor because they have shown that they do not care about us to pull something like this.”

On Camera Audiences, the company that organizes the events, issued an apology on its Facebook page, saying, “Miami. We are feeling your pain!”