How to see packet queues in qmi LTE modules?

I have a Linux box with multiple LTE connections, e.g. wwan0, wwan1, etc., all using the modems' qmi interfaces. If I send dozens of UDP packets, when a modem's antennae are disconnected, they get delivered (many seconds late) when I reconnect the antennae. This shows that the radio is queuing packets. How can I see the size and occupancy of LTE radios' queues from Linux (for LTE modems using the qmi interface)?