Cancel update

Hi.

I've been on version 14.40 for many months now, to avoid all the well-known problems with GPS and altitude of all later versions.
Today, I connected the watch to the computer to charge it (which I never do), and Exopress opened automatically and installed version 19.01 on the watch...

Now, the watch shows me a message that says to update now, or if I prefer at night... but it doesn't give me the option to cancel the installation.
all I could do was turn the clock off and on again.
Now, I don't get that message anymore, but the clock's memory was full... I suppose because there is the file of the new version.
What can be done to cancel that file and recover the space it had before?
It's very annoying, that he did all that without my giving any permission.
thank you very much as always!