I installed the stable NVDA 2019.3 version. When I restarted the machine, I found the version number from the subject line, that's to say, 2019.3.1. My decision is not to install it till I've been told to by those who can tell so.
I use Windows 7 operating system.
I've checked all the mail messages, and found that none of them says a word relating to 2019.3.1. Due to the fact that I've been using NVDA for a longer period of time, let me suppose that this may be a minor version addressing some bug fixes.