I don't think it is the summer, I get traffic from other sources as well, and none of them is behaving like it. It might be something in the system. I will send them an email and let you know when I get an answer.
I got an answer from them, they say everything is ok in their system and of course they are improving every day... This is not what I see. In my stats it is clear that 7search traffic is going down. The quality is still good but the volume is low.