This may cause an issue during normal use.
As the BT hub is not seeing a VDSL signal 4g will kick in and there is link between the SIM (IMSI) and line identity.
If data is being sent on the line and 4g is also sending a connection request the management system will see conflict and raise an exception report. The back end systems are designed to look for abuse and even though this is not, problems could occur.
Simplest way is to use the BT hub, in bridge mode, as the primary connection and the Draytek as router and switch.
I have been through various 4g Assure issues including an incorrectly assigned SIM. Once correctly recorded, everything worked fine.
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