Unable to reach shelly needed services, unable to see FW upgrade, Connection pending in app

[ProsumerNL]

Hi,

I'm off grid setting quite some shelly-pro's up for my house and I am using now a 3G/4G WIFI router to have internet access. (with my phone and notebook I can do everything) but the shellys can't apparently.

I was unable to properly setup the devices and upgrade the firmware from 1.1.x to 1.3.x to 1.4.x  At another WIFI spot, from a different provider I was able to see the updates/upgrades and also possible to setup the shelly like it should. 

I expect some webpages are not accessible to the shelly. Can someone provide me with the network addresses it is trying to reach, so I can test if this is really the case. This is easier than having everything setup to get wiresharking. 

I need to get everything working with the 4G router since the direct LAN/fiber connection can take some time still to get it installed. 

Cheers,