MQTT requires upgrade of current plan?

I haven’t played with MQTT before, so I was going to take a look at what it would be to utilize it. I found this page under the Place settings, but it says I have to
“Please contact us for upgrade of your current plan.”
AirGradient

Is this the only way to configure it, and there is now a new tier to subscribe to?

These should remain in the free plan. We will check this.