apt-mark hold issue (apt Installed: 1.8.2 armhf)

[Michael Howard]

I've not used apt-mark much (or it's previous methods) so I'm a bit 
confused by what I'm seeing.

If I use 'apt-mark hold <package1> <package2>' and then 'apt-mark 
showhold' I get '<package1> <package2>' listed.

If I then do 'apt-mark hold <package3>' followed by 'apt-mark showhold' 
I get only '<package3>' listed. This can't be right, surely?

Am I missing something?

--
Michael Howard