We face similar problem, AT&T start be more restrictive ? like he not be before…
We use Quectel who should work out-of-box, but recentry we see that units must change imei to recovery internet, symtops are like yours, you see connection without internet.
Out detect-internet-and-fix it scripting do stuff like re-enable interfaces etc, try disable Cell Lock, try all Bands, try all APNs 2x, try reboot, try all APNs 2x , try IMEI, repeat from start.
We have sometime notification that internet is back after change APN, common should be broadband but some units detect internet at phone sic!..
Praise MikroTik for scripting feature 
PS. USA Quectel sell units cheaper then AliE and that way we have original products who have certification and should work.
About R11e-LTE-US, we not use it but at start point we know it’s work.