Exchange 2019 / http redirect

Question

Hi all,

My environment was an exchange 2019 with CU7. I upgraded this after the issues in march, to CU9 and the hotfix. Before the upgrade, http->https redirect worked fine, all setup in IIS was all done and ok. Also forward webmail.server.com -> webmail.server.com/owa worked fine

After the upgrade and patch all these settings are set to default in IIS (default website and exchange backend). But I discover some strange behaviour and want to check with you before I reconfigure IIS again for http-https forward and forward to owa

At this moment:
http://webmail.server.com gives access denied . Thats should be ok as that is configured in IIS now. No http-https forward
https://webmail.server.com gives owa and I can login. That is strange, as I have not configured that in IIS
http://webmail.server.com/ecp gives redirect to https and I can login to ecp. That is strange as I have not configured that http to https redirect

Seems something strange happening in IIS so I am little bit scared to change the settings in IIS to what it must be (http-https redrect and to owa)

Thx