Service upgrade #107: Software upgrade FID600, or FID601 should be downloaded to ensure proper overall transmission shift function performance, and or shift quality. It's not like the Volvo dealer didn't get copies of their own service bulletin...geez, who have they got working in their service department? Yes, certain problems can get worse in colder weather. A fluid will be more viscous and slower to circulate in colder weather, loose connections can get looser as the connectors contract, and then once they warm and expand they make contact again...yep, we all should have paid more attention in 8th grade science class.

Not sure if that is all of your problem though...have you been getting a check engine light at all? Just about everything in the world, or at least in the car ties into the electronic throttle control unit. It can get dirty and cause numerous driveability problems, as well as actually fail. Hope this helps.