In order to change the preferences (eg which periods are locked off) all the windows need to be shut down.
This is not helpful when you are 30 lines into a General Journal and go to save it onl...
It's not a question of someone knowing better. AR2013 is a different program, and what could be happening is that various information is provided to the invoice window (and any other window) when it opens, so in order to refresh that information, the window has to be closed and re-opened. Version 19.x and earlier versions stored preferences in memory so that a change to preferences was instantly available across the program.