till/until Doomsday
From Longman Dictionary of Contemporary Englishtill/until Doomsdaytill/until DoomsdayinformalLONG TIME for a very long time You could wait till Doomsday and he’d never show up. → DoomsdayExamples from the Corpustill/until Doomsday• You can watch television news programs from now until doomsday and never come across any statement about Manny Freebus.• Of course, if you choose a male tree you can wait until Doomsday and still never see a berry.• You could wait till Doomsday and he'd never show up.