I do not know what the reason is, but the schedules are visable for not logged in people, except for me as the primary admin.
They are invisable for pilots, if they log in.
They can see the schedules as long as they are not logged in.
I have created a test-pilot so I could test it.
And even if I add the admin group for the test-pilot, it stays invisable.
However the script that Pharko shows routes per airliner only shows if I am logged in.
I think this is related to each other. So I deleted all of Pharko's scripting, but that did not solve the issue.
I guess there must something else going wrong.