回複：urgent: ask for help

I am not an expert. But I have the similar situation and read a lot of post recently. I will try to answer your question.

So if I use EAD card obtained from I-485 filing, can I change back to H1-B later on? Will that hurt my 485 application?
As I know, once you used EAD, your status is AOS. You can only change back to H1B by 境外簽證.
If I do not have H1B and do not have a job, how long is the time limit for such status? Does that hurt 485 application?
As long as your 485 is pending, you are legally stay in US.

Try to be relax. The hard time will pass and good luck!