Thanks a lot for all the feedback.
As Amit, and as well Amir, pointed out, we will look in different aspects of the upgrade notice and workflow, so to try to satisfy everyone.
As Amir points out, this version (free) of Types will continue to receive bug fixes and security updates on WordPress through 2018.
By end of 2018, the plugin will start to show those messages that say it hasn’t been updated since… or that it wasn’t marked as compatible with WordPress since version xy… as an unavoidable consequence of the termination of our development on the free version by end of 2018.
Hence, by then, most likely other solutions will have to be implemented, if the paid Types option is not a viable solution.
I am mentioning this, because while you can keep an updated plugin for now (even if you remove the notices with some custom hack), it will not be possible (and not safe) to “hide” the fact the plugin is outdated, after 2018.
I personally recommend to evaluate what you “got” from Types until now, and to think about, if you are willing to pay for these features (and more), or not.
If not, then I recommend to start looking out for similar, still free solutions.
It will be a required step anyway after 2018, unless you would “support” your own version of Types.
To conclude, we will look in smoother ways to present and communicate – but we cannot avoid the fact that the Free Types Plugin is counting it’s days.
I hope I did not leave any doubts.