The Extended missions essentially just tie up loose ends and finalize the character arc.
It seems Harebrained schemes plans their Shadowrun campaigns around bringing newly created characters from rags to top runner. As soon as the character starts to really kick ass, they don't want to use him/her in another campaign.
With the new mini-campaign, they shovel a few more Karma points on the already too strong character, but the campaign predictably ends with a (choice based) written epilogue that does make clear that the main character's voyages are essentially over, and that relationships with the team members have reached a final state.