Here's the environment: build 672 on three RA servers, each with ~20 clients. Most of these clients are v2.7, but a couple are v3. On the RA server themselves, one has v3, the other two have 2.7 clients installed. The problem is that none of the v2.7 clients will update from v3, either from the RA HTTP or from the v3 client mirror. However what's most confusing is that rather than give any sort of error, it reports that the client has been successfully updated, but to the same sig version that was already present - see attached screenshot. I've ticked the 'create v2 update mirror' in the RA too. I can go back to a pure v2.7 -> 2.7 chain and everything works perfectly. I've tried deleting caches & updfiles contents & mirrors & restarting the RA service in all sorts of combinations and orders but so far no luck. Any further ideas, or a precise walkthrough of what needs to be done (on the RA server, as the clients are clearly perfectly functional...)?