On the way to work this evening in heavy stop-start Auckland traffic, I encountered a shift selection problem whilst attempt to shift from 2 to 3 in tiptronic mode. I tried several times whilst backing off, without success... slipped into D and which then selected 4. Was doing about 2800rpm at the time and had done a trip distance to that point of approximately 12km. It is the first this has happened Once i had joined a road with no traffic and had an open road the same shift 2 to 3 was executed as normal and appeared back to normal with another 10km till I arrived at my destination. The ambient temperature was about 12oC and am wondering if this is symptomatic of an overheating AT, confused transmission or something more sinister like death? (I have done about 500km since my last ATF flush / replacement).