Dems are changing their talking points daily.
I don't know why you guys are pretending you're lawyers or pretending this is a legal proceeding. Impeachment is a purely political procedure by design. An impeachable offense is whatever the house says it is. I believe it was Gingrich who when asked why are you impeaching answered "because we can".
So I've only been making two points...
First, I'll believe Dems are actually moving forward with impeachment when they take a floor vote and put their vulnerable members on record. Until then I'll believe they are just hanging the impeachment carrot in front of the base as they have been doing since Trump took office.
Second, I think Dems are losing the public relations battle to get enough support in the country to make impeachment politically beneficial. I could be wrong. This is the only thing Pelosi is trying to figure out now.