I recently learned about the mv -t flag option in bash, but when I checked the man pages on my computer, there was no mention of it. The man pages were dated 9 July 2002. I ssh-ed into another UNIX system and found the mv -t option in the man pages there, dated December 2015.
I reckoned my bash shell needed upgrading, so I upgraded from version 3.2.57(1) to 4.3.42(1), following the steps here: http://clubmate.fi/upgrade-to-bash-4-in-mac-os-x/
Now when I run "echo $BASH_VERSION" it says "4.3.42(1)-release", but if I do "bash --version" it returns "version 3.2.57(1)-release". The man pages are still from 2002.
Any ideas what could be going on?