Two, I think the musical episode would be saved for May sweeps. May sweeps technically start on April 27th, which should make 619 the first OUAT episode of sweeps. So I’m thinking 619 or 620, as I doubt the musical episode would be the finale.
Well, this could still be part of the May sweeps if they decide to take Easter Sunday off this year. Although I don’t know how that would fit with the schedule but let’s face it- ABC’s schedule has been all over the place this year.