I have a PA4010 + WPA4220 kit. I updated PA4010 without problems and in tpPLC utility I can see that firmware version has indeed changed. However, on WPA4220 I get the message that update was successful, but firmware version stays the same. I tried updating via utility and web interface; doesn't make a difference. Firmware I'm trying to upgrade to is official with matching region and hardware revision. I also tried downgrading to older firmware and got the same result - update is reportedly successful but device always returns the same version (1.4.0.20-00_422015_200108_901) no matter what. Why am I stuck with factory firmware and is there something I can do?
Similar issue here. However, I got around your problem by using my smartphone connectivity/interface rather than the computer. I noticed, as the WPA4220 was attmepting to reboot, it would go offline, and my phone would reconnect to my router. By literally reconnecting to the WPA4220 as it came back to life it seemed to make things stick.
Hope that helps?!
As for me, is there a firmware upgrade for the PA4010 ? I don't see it on the relevant page below? [Here in the UK]. Does that mean your firmware is for somewhere else in the world? 
