I've had two experiences recently with Upwork that gave me a lot of pause. In both cases it was clear that the people I was talking to had nothing at all to do with the record of work, feedback and billing that I had reviewed. In both cases there were also strong signs that the person was not located where they claimed and were not fluent speakers of the principal language of their locality. In one case I'm pretty sure they were using a Text to Speech engine once I demanded a Skype interview. Both wriggled out of video interview for different reasons.
I know that there are simple ways to avoid these traps. However, I also know that once these trends set in, the approaches become more sophisticated. So I'm concerned that Upwork may really no longer be safe to do business on.
After all, if someone who seems reasonably legitimate and has real feedback is willing to sell their Upwork credentials, then what else would they be willing to sell?
That was a silent change in the client update.
Now thanks to your info I believe we can connect the dots - people are using Upwork for undisclosed subcontracting.
EDIT: Out of curiosity, what kind of work were you hiring for?