Hi,
IvozProvider's queue support is quite basic, as vPBX was not the primary focus of the solution when it was originally developed.
It does not include queue statistics or advanced behaviors out of the box. However, you might want to explore Asterisk's queuerules, which can be configured in a single file and may help you implement similar logic.
For example, you can have L1 and L2 agents in the same queue with different priorities. The system can be set to ring phones at one priority level for a few seconds before moving on to the next level.
You can refer to this sample configuration for more details:
https://github.com/asterisk/asterisk/blob/master/configs/samples/queuerules.conf.sample
Best regards,
Kaian