Duly, if you plan for Infopass, you may schedule one right away - the officer at the window has access to the whole case information and will be able to tell you when the interview is and even print a copy of the interview letter for you. This happened to me with the fingerprint letter when I went to an Infopass appointment unrelated to my N-400. After I was finished discussing this other matter (temporary evidence, I did not have my plastic GC), I asked about the N-400 case and she printed me a letter three days before I got it in the mail. I bet it is safe to assume your interview is already scheduled since you were ahead of me on the case transfer date.
Do let me know what you find out! So far I learned they can expedite the case when there is severe financial hardship to an individual or a company, but need to travel does not qualify, as you may easily travel with a visa anywhere you might need an American passport, and as far as attending the interview and oath - they may be rescheduled if they fall on the travel dates. That was the tier 2 response to my "expedite" question.
I will be really curious to know if there is a way to expedite the oath itself. So far my understanding is that Houston does not do administrative oaths other than for someone unable to attend judicious ceremony for physical reasons.
