Seaplane crashes May 11 1940

[Pieter H]

I have reports that on a single day, May 11 1940, no less than 5 He-115's crashed at/around the island of Nordeney after mine laying around the dutch isles of Texel and Vlieland. Three from 3./KüFlGr906 and two from 3./KüFlGr506.

What surprises me is that 5 planes crash on the same date around their home base, although apparently all hit by anti-aircraft fire over the target area. So is this not a case were the accumulated losses of the first 2 days of fighting were reported together and attributed to their base, instead of the actual dates and locations of the losses?
Also because for these same dates there are several reports/claims of what seem to be seaplanes being downed over Holland, but which I don't find in the german loss reports.

Can anybody help to clarify?

Pieter