I would say nope. The slave is tied to the clan eg. Say tremere or tremere anti slave. So changing sects wont change your clan or the slave trait that ties you to that particular clan.
The slave trait is not linked to the sect nor the clan so it doesn't go away when the vampire with this trait changes sect or clan.
> rulebook wrote:
> Slave: Some minions are identified as slaves to a specified clan. A slave cannot take a directed action if his controller doesn't control a ready member of the specified clan. Also, if a member of the specified clan controlled by the same Methuselah is blocked, the controller can tap the slave to cancel the combat and to untap the acting vampire and have the slave enter combat with the blocking minion instead.
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Prince of Paris, France
Ratings Coordinator, Rules Director