Fans who have been waiting years for Fiona Apple to return to Washington will have to wait seven more days.

Fiona Apple performs at the NPR showcase during the SXSW Music Festival. (Jack Plunkett/AP)

The resurgent singer has postponed Wednesday night’s performance at the Sixth & I Historic Synagogue until March 28, according to an e-mail from her label that says Apple’s bandmates have fallen ill.

I had the chance to catch Apple launch her comeback at SXSW last Wednesday night. I wrote in Monday’s Washington Post that the 34-year-old “was one of many old pros hoping to bounce back into the vanguard at SXSW, but she sounded fidgety and freaked at Stubb’s Bar-B-Q on Wednesday. During new songs and old, she frequently replaced her plunging contralto with feral snarls. “You’re imaginary,” she told the audience at one point. “You’re not real.””

Promoters say tickets for Wednesday’s concert will be honored on the 28th.