Good news – I did some testing with 3.3.9 and it looks like the issue I originally found has been resolved.
Bad news - I found another weird issue when pressing ESC after editing the symbol text at the mockup level (vs. editing at the symbol source). It is very similar to the original, but requires editing the text to cause the problem.
Follow the same steps 1 through 4 from my original post.
For step 5, edit the text for Products and change to Prodqucts then press ESC.
For step 6, exit the symbol
At first glance, it appears the changes to the text were not saved. However, when you back out of the symbol, the changes now appear. Not only that, but the Links, and Text are now set to overrides.
The default action for pressing ESC throughout the application is to revert back to the previous state and ignore any changes. This is not the case for the Symbol text override.