Hi Vijay,

>> That is still an assumption that needs to be confirmed. So 
>> does the default context activation from just uses APN == "" 
>> and then the network picks the APN to activate. Or does it 
>> just use the APN value from CID 1 for example.
>>
> 
> At this point , if the returned cid is out of range it is assumed this
> would be default context (already activated).
> Network has the APN and other required mandatory parameters required for
> activation of default context.
> This is done part of implicit attach process.
> 

What Marcel is driving at is this comment from 27.007:

"The <cid>s for network-initiated PDP contexts will have values outside
the ranges indicated for the <cid> in the test form of the commands
+CGDCONT and +CGDSCONT."

Please do note that default EPS bearer is not network-initiated.  It is
ME-initiated.  So I currently see no basis for your assumption.  Have
you checked how existing LTE modems actually do this?

Regards,
-Denis