I've had it on a CP10, twice. I usually do the updates via WebPro but the last couple have hiccupped. One time I was able to push the update via PcPro and the system rebooted and came back to life. Second one, it would not reboot and could not get system to recover. Luckily it was my home office system and had a used CP10 I could use, until NEC is able to start shipping CPUs again.

To say the least, I am a little gun-shy now about doing updates after having two in a row fail.

Why would you have to wait till they start shipping CPUs again, Can't you just send the bricked one back to have it recovered?

When I was speaking with NTAC, they did not offer for us to ship it in. I am guessing as it is out of warranty, they want me to purchase a new CP20.

They have replaced a couple CP10s back in the day when there was the issue with bad SD cards causing the CPU to fail, but have never been given the option to send one back to be recovered.

You should ask, I'm fortunate in that the local NEC office has someone who can both recover the CPU and reset the Demo License. But it is a service they should offer especially when new CPUs are not available. Apparently it is quite a simple operation, You aren't asking them to replace the CPU just recover it after a failed upgrade! It could be argued that it was the failure of their firmware that bricked it so they would be obliged to help.