Readynas Ultra 6 freezes (case: 18799893)

Readynas support suggested it could be a firmware corruption issue and to redownload and install the Raidiator image. I did that (in the meantime 4.2.21 was released, so I upgraded to that) and I haven't had the device freeze up since then (it's been 6 days). I don't know if I'm out of the woods (the previous 2 crashes occurred after 2 and 7 days of uptime, respectively) but we'll see. Incidentally, is there a quick/easy to see the uptime of a Readynas device? I feel like this should be an option in Frontview or Raidar but if so I've missed it.