Firmware update running for two hours and counting

I have a 16TB My Cloud Ex4100 configured in RAID 5. This afternoon I updated my firmware and ever since the power light has just been blinking blue and the unit says “New Firmware is Available”. This has been going on now for two hours. I’ve updated firmware before and it’s never taken this long. Anyone else experienced similar?

Update: After 10 hours in the same state I finally made the decision to power cycle the unit. However, even trying to turn off the drive by holding down the power button did nothing. So I unplugged the unit, waited 30 seconds and plugged it back in. I’m happy to report all appears to be working and firmware is updated to 2.30.181.