Blue Muffin viburnum question

[Clint62]

Last summer I planted 1 of these, and when it came to life this spring, it grew new branches that are wayyy higher than other branches . I'm not sure if I should prune the taller ones so they match the height of the others now, or wait to do it after the flowers are done..(supposed to bloom in early june). Just trying to not make a hasty decision lol

Thanks in advance.