Python Pyinstaller - How do I customize a program I have created?

I created a keyword search tool in Python and then converted it to .exe format using Pyinstaller, so people in my workplace could use it without installing Python.

I emailed this to all users in a RAR file, which was then saved to their desktops.

I'm thinking of some potential tricks I could do for this, but I don't want them to keep sending them the complete program every time I decide I want to change something.

So the question is, is there a way that I can send the patch file to update the program? What should I be looking at?

Thanks in advance!