Board Thread:Questions and Answers/@comment-25660412-20151106113242/@comment-7503158-20151106113934

They travelled back to the time before the bomb was activated. Vilgax said and I quote "It is designed to wipe other timelines from existence", assuming he means the present time before it was erased, we can assume it is still in tact in the past. Plus, it was never said the effect was permanent.