Hi,
Where get previous version for MikroTik Chateau LTE12 , which is comes with router from factory, namely : 7.0beta8
we bought 5 Chateau, one of this we upgrade to last beta version.... now its just a plastic box with not correctly working lte modem.
other one, with older version working perfectly.
Alex

Write to support.
The first firmware for Chateau on the repository is the 7beta08.
https://mikrotik.com/download
The 7beta06 preinstalled from factory isn't on download page.

You have to upgrade the firmware of the lte modem from version 04 to 06 too.

I don't have problem with Chateau on 7beta08 (plus firmware 06) on Wind3 lte network.