I’m concerned about this point as well. I own licences for repeater and options page. I have a couple of themes under development using both addons following the guidelines.
I know I’m embedding the plugin within my theme but what would happen if WordPress is updated in the near future and version 4 does not longer work?.
I got a complimentary personal licence of ACF Pro which I’m thankful for but I cannot use that for my themes development and future compatibility of WordPress and ACF4 worries me a little bit. I’m was able to use my addons anywhere but with the introduction of the new system and my personal license I wouldn’t be able to do anymore if ACF4 fails at some point in the future.