6:02 AM EST - S3-E20
Continuity mistake: This is after Olivia has bumped into Walter in the hallway. She gets back into bed and tells Peter that his father is walking around the house naked. Peter laughs and says it's normal for a Tuesday. The sun is on Peter's left cheek in shots from behind Olivia. In the reverse shots from behind him, the sun is missing. (00:07:30)
Answer: In the time line of Season 4, William Bell is trying to destroy both universes to create a new one, and he needs Olivia to power the collapse. So he helped her escape. But the real question is, if not in search of Peter, why Olivia has to travel to the alternate universe to be captured and replaced?
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