I did an American Eagle flight connecting with CX in LAX and HKG to SIN. The ticket was open, and there were stickers on each coupon. I had no problem checking in and getting boarding passes for all my connecting flights too.

Seems to be this reissue thing is to prevent people with nonref, nonchangeable tickets to just show up at the counter demanding to be let on. But it slows down the real people with legitimate open tickets for travel.