Have you reached out to Linda at Mail's Best Friend regarding this? She's on here, maybe she can respond. 

The product is end of time since a long time.

That's true, but they may have some insight or suggestions. As far as I know, Mail's Best Friend is still supporting it as much as possible. 

Yes, it's rules engine and extensibility make it a beautiful tool for anyone who wants to control their own destiny.  Declude Reboot is its only competition.  I will make the switch eventually, but the old version runs so well!   I have prioritized development of more customizations over making the switch.

Hey Martin!

Please send me an example of this directly to my email address. We are happy to look at it.

Thanks!

Hey Linda

That's great. I'll send you a sample email this evening.

Cheers!

Is Declude Reboot a thing yet?

I've never seen it available.

My experience is that it is available by request, on Window with Smartér Maul or Linux with PistFix as the MTA.  I have tested but not yet switched, largely because of a mixture of fear, inertia, and competing priorities.