I've had a middle-grade manuscript sitting (or standing, or whatever manuscripts do while they wait) at a small regional publisher for going on nine months now. It was requested last summer just a few days after I queried, and I received an enthusiastic confirmation e-mail a couple of days later. After six months of silence, I sent a brief follow-up to check on the status and got no reply. I've since seen on the Web site that the person to whom I was asked to direct the manuscript is no longer with the publisher. I would assume that when the intern/associate/whatever who was originally assigned the manuscript departs, the manuscript remains viable until I'm notified otherwise. Is it OK to e-mail the managing editor, who originally requested the full manuscript, again? How might I word the e-mail to engender an actual response? I don't want to be a stalker, but this isn't a slush pile situation. They asked for my book.You're not being a stalker. They ought to respond.
However, one of the staff leaving often means his/her to-read pile is utterly orphaned. (Possibly even orphaned into the recycling bin.) Anyone helping to shoulder the work that staff member left behind is going to have more than enough to do with the already-signed-up manuscripts.
I would suggest you do email the managing editor, but there are no magic words to make this a priority or ensure a response. Meantime, you should be submitting elsewhere. 9 months is ridiculous.