After I updated AE today I was able to work with a project WHILE it rendered. Not the rendering timeline but anything else, it seems. Is this new, as I suspected? I knew there was a way to do this manually with AERender but now it does it right out of the box. Great time saver.
are you sure you didnt open up a different version of after effects...or maybe it instanced after effects while updating...so it allowed you to work on a copy ...but you always have had the option to open up 2 different version of AE at the same time...it just doesnt work very well