Retire & Rally

Hi everyone,
We've been playing last Friday Sherifmuir which scenario contains some Battle Cavalry units. I'm thinking that we made a mistake with the Retire & Rally rule.
The question is simple : Can a Cavalry unit Retire & Rally when it is attacked by an enemy Cavalry unit ? 
When I read once again carefully the rules, it's not written that the attacking unit is an Infantry one. When playing TAR, this situation didn't occur due to the little presence of the Cavalry units, but it's not the same in Jacobite Rising.
If you have an answer, I'm waiting for it.
Greetings from Le Mans

It appears prima facie to me that cavalry can retire from cavalry. There seems to be no unit restrictions based on attacker for this ability. Light infantry, Light cavalry and Battle cavalry appear to have unrestricted use of this ability, regardless of attacking unit.

Thanks Mark for your answer.