I have not upgraded Sonar for a long time but I'm seriously considering getting the Sonar for Life $199 deal. My problem is that I want to wait till Apple makes it's hardware announcements (hopefully in September) to see whether I want to upgrade my computer, and that decision will affect whether I need to upgrade Windows for Bootcamp, etc. Anyway, even though I would want to purchase Sonar before the Aug 31 deadline, it may not be best for me to install it right away.
 
Is that in any way a problem? Does the software need to be installed/activated by the deadline of August 31?

Hello,
Once you buy it you own it. You can download it any time you choose. Or not download it any time you choose. It just sits waiting for YOU.
MJ 

There is nothing to install as far as lifetime membership. Its noted in your account. If you use CCC as most do you don't have to run it if you don't want to. However if you are on a Mac CW is coming out with a Mac version that is an option at no extra cost. What this means is you are covered no matter what you choose except not going for the lifetime membership.  

One caveat.
 
If you buy the Sonar upgrade from a distributor, as opposed to the Cakewalk store, you will receive a code to enter into the Cakewalk servers to register the purchase on your account. It is likely that you will need to do that before the Aug 31 deadline in order to get the lifetime update registration. Unless Cakewalk has provided a special set of codes to the distributors, the key issue is the time that you register with Cakewalk. Once your account has been registered as having the lifetime upgrades, when you download and install it on your computer should not matter. 

When you install makes no difference. The early purchase just entitles you to the special deal.

Thanks for the replies. I'm going to order it Monday.