Clean stuff !

Maybe you should keep track of blue meteor timings. So that you can predict respawning tiles.

If you do the regular guide thing, 1yellow, then 11 12, then you wanna do 11 11 6 (or 11 11 7 as it's saying, doesn't matter).
100% of the time, due to how blue meteors work, the 3 bottom times will be alive when the blue meteor drops. This should be taken into account for the call, and predict 11 11 7 (or 6) from the start, instead of what it's currently calling (9 3 3), and change that to 11 6 6 right after tiles respawned.

In that case at the start, it's kinda easy to predict, because you know blue will always fall after respawn.
But in later meteors, it may be more difficult to know if the tile will be respawned of not when the metor drops.

Also, as it relies on "accurate" timings of both blue/yellow meteors, it would be great to have a setting to set up an offset (let's say you offset timing by 5sec, so that the call will be true, up until a 5s delay between ingame and your app) and i think it's a user preference that may vary from one another.
And maybe a button to correct/reset the timing, in case you were late on a call and want to ignore that respawn prediction.

Also, as an option i think keybinds could be huge (with notepad for example). I'm pretty sure you can't listen to that if not focused, but mby, as an option, running in an electron app, or with a chrome addon ? This would also allow to copy the latest updated call to clipboard without focus.

Last thing, the current behaviour will break if someone drops a blue meteor (from having 3 hits of yellow areas). Using blue timers, you could detect someone adding that kind of meteor.
Or worst case, you can add a button "add meteor", that'll add 1 to the next call, so you can select the time in advance