I've used RUT240 for some time now. I had a couple of them working completely fine in a private APN but i found a problem in a newer batch.
The problem is that the RUT240 cant connect to a private APN (same APN used for working RUT240 models).
I checked the hardware revision, rut firmware, the modem and the modem firmware and everything is the same. The SIM card connects to the mentioned private APN with other devices, but not with RUT240.
Im attaching the system log in which the problematic connection is shown. The R10_30 is a regular working RUT240, and the R10_31 is the problematic one.