RabbitMQ Management wrong consumer count

Question

I'm using RabbitMQ 3.8.9 with Erlang 23.1.

From the web management panel, queues page, I have enabled the "consumers count" column.

When I start n consumers, after a few seconds, as expected, I see the number in that column increase by n.

The problem is that the count does not seem to update always correctly.

For instance I know for sure that a queue (in-aws) has no consumers, because the machine hosting the consumer is down, but still I see the old number of consumers.

Am I missing something? Thanks a lot