Could just as easily be A4, just because you see 'workers' with 250-280 mh/s that doesn't prove anything.
Using the Nicehash chart, they've been averaging 251Mh per miner (40728/162) for the last 1.5 hours. That's pretty close to the L3 specification of 250MH which would incline one to believe these are L3s given the A4 instability issues.
Given the MHs spread per miner I'd bet on them being A4's. Looks a lot like mine do.
Someone's trying to get better returns following the big profit drop this week.