RAK7249 vs The Things Outdoor Gateway

I’m not ready to install either of these gateways outdoors where they are difficult to reach. I recently discovered why my TTOG’s LTE went offline: it ran out of data because it uses 30MB-60MB per day.
See: Things Outdoor Gateway - TTOG part 1
And: Gateway data usage

The RAK7249 also ran out of data and the pictures looks even worse:

Description Session Start Session End Usage
Afrihost APN Usage 2019-06-10 2019-06-10 00:00:00 2019-06-10 23:59:59 607.14KB
Afrihost APN Usage 2019-06-11 2019-06-11 00:00:00 2019-06-11 23:59:59 1.28GB
Afrihost APN Usage 2019-06-12 2019-06-12 00:00:00 2019-06-12 23:59:59 2.01GB

Taking into consideration that previous tests indicated about 3.5MB of data usage per day for a normal UDP based gateway these numbers are way out. I need to get this fixed as running a gateway at this data usage will become expensive.