I updated my installation to PN 1.4 without issues (using some favorite lines of PowerShell). When updating Jetpack to the latest, 4.2.2, I did encounter an issue. I was getting an error similar to:
Warning: require_once(/somepath/jetpack/somefile.php): failed to open stream: No such file or directory
(Some old discussion: https://wordpress.org/support/topic/fatal-error-with-jetpack-293/ )
I tried via GUI a couple of re-installs, but finally it took a deletion of the jetpack plugin directory and a manual upload (thanks Webmatrix) of the latest download to resolve the issue.