Surrender green card and reapply after marriage - Does I140 expire?

[md12345]

1 year ago I got a green card.

I got 2 approved I-140ies: one in the EB-1A and one in the EB2-NIW category.

Subsequently I went ahead with adjustment of status based on the approved EB2-NIW (simply because it arrived in the mail earlier than the EB1A).

Got a green card (strangly the code on the GC reflects the EB-1A although I used the EB2-NIW I-140 for adjustment of status, but I guess that is irrelevant).

Now I want to marry a foreign national.

I refuse to wait 3 years for her to get a visa.

QUESTIONS:

1) Can I get married, surrender my GC and reapply for adjustment of status for me and my wife based on the "unused" I-140. or do I have to re-apply for the I-140? I read somewhere that the I-140 doesn't expire. Or is that only true if you never go ahead with adjustment of status; In other words: Do all I140ies expire after adjustment of status - or only the one "used" for adjustment of status - or none?

2) I actually read somewhere that I wouldn't even have to surrender my current GC, but rather re-apply for consular processing adjustment of status and than re-immigrate once approved. Is that true?

I appreciate any comments.