Verizon Galaxy S3: worked fine for a week on 4.3, then 'no network' topic

I installed custom 4.3 ROM from http://forum.xda-developers.com/show...hlight=no+data and all was working really great for a week. Then today for some reason I got no network - can't call, no mobile data.

On local wifi everything works well. Reboots, power downs did not help.

Has anyone experienced anything like this? Any tips are greatly appreciated!