Ahmed,
As far as I understand it, it’s just another term for ‘Remix’…
Whereas Dub’s tend to be missing vocals or completely different sounding ‘Bassy’ versions of the original track, Re-Rubs tend to be much the same as remixes.
See also:
Re-Fix
Re-Lick
Version
Update
Booty
Bootleg
etc etc etc…
It’s all open to interpritation, I’m sure others will have a different explanation…
D