XMR Pushfrom a cms on the internet to multiple clients behind NAT

Hi,
can’t seem to find a answer before going through all the hassle to install extra pho extensions.

I want to have a CMS on a public webserver on the internet and i have 3 players behind a adsl NAT Router.

Does the push notification work or do i need to create a onpremis server?

The Players connect to XMR over a long-running connection, so the Players being behind a NAT should not be a problem.