This isn't exactly true. If a blue beat combo continues, it continues under it's usual hitstun of the given attacks in the combo, barring the hitstun and proration hasn't already gone stale. So lets say your opponent simply mistimed the next attack in his combo, it may have blue beat, but the combo would continue as it normally would. Just for reference, a blue beat combo is when something combos that shouldn't have, the reasons vary though.