Dave, I'm not sure if you have the same problem. It sounds a bit different.
The only problem I have is that when the computer should be sleeping, in other words, when it times out or when I close the screen, it shuts down instead of sleeping. And it doesn't matter if it is plugged in and charging or not, it just shuts down.
For my pc, the power drain simply meant unplugging it and holding the power button in for at least fifteen seconds, and they just made standard changes to the sleep settings.
However, it doesn't matter what they did, because it seems to have just been a temporary fix. The problem has returned.
If I can find another hour-and-a-half to call HP again tomorrow and go through all the stupid questions like "And do you want your notebook to be able to sleep?," then I will call them and complain again, if the problem has not somehow righted itself by then.
I kind of think that they have their support representatives playing stupid about the problem. One responder here found evidence that this issue actually started in beta testing, over a year ago. And my thread here and on the Windows 10 forum have tons of replies, almost all from HP Pavilion and Envy users. Plus there are about a million other threads about the same problem.
Luckily, my computer is still is under warranty, and I can even still purchase extened coverage, because they sold me this computer under the guise that it would be Windows 10 compatible, which it obeviously isn't.