Nora and Rhys manage to leave the Banks' mansion without anyone suspecting or even seeing them. They met with Hugo and Wesley a couple of blocks from the mansion and then Nora instructed them to drive towards the headquarters of the Twelve Army.
Rhys didn't question her because he knew why they were going to the headquarters of the Twelve Army.
It was already time for them to meet the others for a gathering since it has been a while since they have done that. The last time was when Megan left for Crocus and since then, they felt that it was not right to hold a gathering with one of them missing.
They have never spent a gathering incomplete. Except for when one or two of them were training at the Twelve Army and were not allowed to leave. So, they just waited for Megan to come back.