"No, I don't think he'd dare go up against Albus for quite some time," Gellert said. "Albus tells me that Tom was all but shaking with fear when the two ran into each other at Chateau Riddle in the first days of November."
"A concert on New Years Day?" Grindelwald remembered a tidbit from The Life of You-Know-Who. "His birthday is New Year's Eve. If I were him, that's when I'd make my move."
"I admire your pluck, Harry," Gellert grinned, but all warmth left his face. "Take a word of advice from someone who knows first hand: The Elder Wand does not make its wielder invincible, contrary to legend."