auto-version and shared write-locks

Hello,

Let's consider the following case:

A checked-in VCR exists with its DAV:auto-version set to
DAV:locked-checkout.  A user grabs two shared write locks on the VCR.
Then the user does a PUT, including both lock tokens with the PUT
request.

At which point does the VCR checkin automatically?  When both locks
are unlocked or when either lock unlocks?

Thanks,
Tim