I have the 3Gb limit on the radio Broadband, and have NOT yet exceeded 2Gb a month.
I do NOT usually have Process Network Flights enabled, so :-
Upload is ON, Info Requests are on - 1 picture ONLY per Aircraft.
Actual daily figures don't seem to be available, but the software I use - from VodaPhone - gives a running figure of traffic for the session, and in another view Total traffic for the month.