There were a lot in the UK in 1976. We had a huge growth in aphids after a warm spring, the ladybirds followed on. I remember seeing a boat at our local reservoir that was covered in them, even the sails, it had turned from white to read.
Oh yes, the long, hot summer of '76. A glorrious time to be 16 and unexpectedly having the house to myself for several weeks.
But no ladybugs to speak of, over here across the North Sea from you.
Jellyfish, on the other hand. I remember sailing through shallow waters almost solid with them. Also a one-off, never seen anything like it since then.
https://www.bbc.co.uk/news/magazine-35603972