Hello! Before I offer a suggestion, I want to give my thanks to you for updating and enhancing this mod for 2.0. - it's added a much needed spice to my current play-through!

The demolisher attacks on Vulcanus, however, can be a bit too spicy for my taste sometimes but only if I am notified when the behemoth had breached my defense line, so by the time I arrive on-planet my base has been largely destroyed.

I noticed the very first demolisher attack had a unique notification that appeared a little bit ahead of time. Would it be possible to add a setting to allow for this alert before each attack?

Yes, it is possible. The only thing I need to think about is whether the setting should be for each player or be a map setting

My vote is for map setting, thinking that may be better for multiplayer games
Edit: thank you!!!

I would also love a notification one or two minutes before the attack

I's a bug. Or rather, an error accidentally added right before the release. Evolution on Vulcan has become 100% due to an error.

Unfortunately, for unknown reasons, documentation for the Factorio commands is currently unavailable on the mod portal, so a fix won't be released until tomorrow.