Yesterday I've seen an A320 standing at the gate with flaps 1. While this question answers, why the flaps should be up, is there any reason to retract the flaps to 1 instead of up?
In addition it seems to apply only in high temperatures (30°C, and rising yesterday). As well in this pilot eyes video the FO confirms the temperature (31°C) before setting flaps to 1 as they taxi to the gate.
I've seen this only on the A320 (yesterday) and on the A330 (in the video). Does this apply only on Airbus aircraft or as well on others?