I just took advantage of the Studio One crossgrade deal through JRRshop.com.
 
I had understood from Rick Naqvi's announcement at PreSonus that I had to send my proof of Sonar ownership to them :
 

If you are interested in crossgrading to Studio One Professional, you only need to submit one of the following three things to crossgrade@presonus.com.

 
but when I did, I got the follow response from PreSonus :
 

If you purchased a copy of Studio One 3 Professional from JRR shop, please contact JRR shop and they will provide the key to you. You first need to provide your proof of ownership of Sonar to JRR shop. Not to PreSonus.

 
I got the following reply from JRRShop when I bought the upgrade :
 

Presonus Studio One Professional V3 Crossgrade for Cakewalk Customers
License: http://presonus.com/registration/ : This license needs to be manually generated. You will be contacted immediately when it becomes available.

 
What happens next ?  (it's been a couple of days)
 
 

I did the same last night.  Did you add your Sonar proof of ownership to the drop box link on the product page on JRR?

I forgot to add the documentation to the drop box link last night. I emailed JRR to ask what happens next and the customer service person asked if I had added my documentation to the drop box link.  I replied that I hadn't and did so by going to the Studio One product page on JRR and found the drop box link.  It will ask for your name and phone number when you submit your document.
 
I emailed JRR back to told them I'd done so and also included the proof of ownership in my email.  About 7 hours later, I got a note from JRR with the license code.
 

june61944
I did the same last night.  Did you add your Sonar proof of ownership to the drop box link on the product page on JRR?

Thanks june61944 for this information.
 
I hadn't done so, but just now uploaded my info to the drop box link.
 
 

You're welcome.  Just spent the day in Splat, having a grand ole time, but the download of content from Presonus just finished.  I'll open up this lesser DAW over the weekend but looking forward to learning something new.  If anything, I've demo'd a half dozen DAWs and it really came down to SAMP and S1.  SAMP is too much for me - I barely scratch the surface with Splat - but I nearly pulled the trigger.  My only reservation is missing a major update opportunity if a new version is released that pulls together some of the organization/UX I love about Splat and S1.

 
I just received my code from JRR and have downloaded SOPV3.
 

june61944
I've demo'd a half dozen DAWs and it really came down to SAMP and S1.  SAMP is too much for me - I barely scratch the surface with Splat - but I nearly pulled the trigger.

These deals are hard to handle , especially since they won't last forever.  I don't have the time right now to test things out and make an informed choice so I originally went with Samplitude because of the price and comments, and was happy with the choice.  I then made the mistake of reading the threads on Studio One Pro and at 125$, I just couldn't resist acquiring an alternative.
 
I also picked up Overture.

I hope JRR puts this discount back I found out too late about it. The group code still works on JRR.
 
I have been testing Studio One Prime, really nice so far.

I'm glad I got in on this for $125.