This is a totally new airline for me, and I was wondering what it is and where it comes from (Germany obviously, but the name makes me think of Sweden, because of the similarity to the town of Sundsvall probably!).

https://sundair.com/booking/index.php

They seem to have picked up some of the slack from Air Berlin, with flights from Düsseldorf to the Canaries among others. I also noticed an unusual connection from Düsseldorf to Kassel airport on the evening of 03.01 (can be found on the Düsseldorf airport website), which looks interesting! Wonder how long they will last for in these times of folding airlines.

Another interesting thing is that they appear to use the code SR, which is the old airline code for Swissair. Wonder how they managed that, I thought that code was owned by somebody already.