It is my understanding that since BY-SA 2.0 , all CC-BY-SA licenses have included some automatic "or later" clause, which means you can adapt the work and release the result under a later license.
It was recently pointed out to me that copying a work isn't the (necessarily) same as adapting it. Does re-licensing still operate if the work is copied but not modified?
 Relevant link:
Version 2.0 licenses that feature the Share Alike requirement now clarify that derivatives may be re-published under one of three types of licenses: (1) the exact same license as the original work; (2) a later version of the same license as the original work; (3) an iCommons license that contains the same license elements as the original work (e.g. BY-SA-NC, as defined in Section 1 of each license). The version 1.0 licenses required that derivative be published under the exact same license only. Our tweak means much better compatibility across future jurisdiction-specific licenses and, going forward, across versions. Less forking, more fun. (See Section 4b.)
(from "Share Alike Across Borders" in Announcing (and explaining) our new 2.0 licenses)
Alternatively, follow the "More info" link that appears in the "same license" tooltip on the CC-BY-SA 3.0 human readable license.