If you look through history, you will see that they use this path from time to time... E.g. on 27/3, 24/3... It arrived 06:08 (2 mins earlier than scheduled) on 27th and 06:10 on 24/3. This flight appears to be on time most of the time. I would be guessing it has something to do with winds and the fact that ZRH has curfew until 06:00, so they cannot arrive much earlier than ETA of 06:10.
Ironically, it appears that it will be bit late today, currently it is expected to reach ZRH at 06:33.