I have just seen a tweet from Orange Tree that says all the evolution guitar libraries have been updated. Updates should be in your account.

I am looking forward to downloading them tomorrow.

Yep!  I'm very excited.  Have been using Banshee, Stratosphere, Strawberry and the acoustic on every song since Greg introduced the new engine... it's just bliss... 
 
Now to go see what the upgrade entails.... yee haw! Love that man...

Just checked and I don't see updates in my account.  I will wait for the email and see if mine show up.  I suspect they are rolling them out and it may take a few hours to get them all in the accounts.
 

Curious I am.

Well I have just gone into my acount and I can't see any obvious updates but i downloaded the Stratosphere engine files and the NKI is dated 7th September.
 
I unzipped these to a new folder, as opposed to overwriting the original NKI files to be on the safe side. I can confirm this NKI contains the function to send the multitrack guitars to seperate channels, so it is an update!
 
I will try Steel Strings and Strawberry later. I am suprised I have not seen a email anouncment of instalation instructions.

I just looked at their support forum on KVR
 

Happy Labor Day!

We just uploaded new engine files for all the Evolution guitar libraries to bring them all to the very latest version--you can get the update(s) in the downloads section of your account on the website.

Here's the list of changes:

- Additional reverb pedals.
- Improved round-robin.
- Legato is now restricted to only happen within the same MIDI channel.

Depending on the library, there may be additional differences, such as being able to route the multitracking out separate audio channels, etc. But now all four Evolution guitar libraries are at the same version.

No need to redownload the samples. You only need to replace the NKR and NKC file.

Just to confirm I updated all my Evolution libraries. Note, that with the exception of Banshee, the new NKIs have a different name. I have retained both and repaced the ones in my my Quick load list with the new ones.