Squishy Deadlines

What is a deadline, exactly? In the program brochure, they seem so strict: Failure to make adequate progress will get you ... I want to say "expelled", but the language is more like "asked to leave the program". In real life, however, they aren't so strict. First there was a general consensus that, due to a probable typo in the guidelines, "by Month" really meant "by the end of Month". Everyone gained a 30 or 31 day extension on deadlines (there are no deadlines in February). Several of the master's students are being granted informal extensions on the grounds that their advisors were travelling during the critical pre-defense period. Only my advisor seems to break the laissez-faire attitude in our department by insisting on keeping deadlines or requesting formal extensions (when she's aware of them, which isn't always).

Now another grad student in my lab and I are in a small dance of deadlines. She started a year before me, but due to extensions granted to those pursuing a double-major PhD (I am not so dedicated), we are both due to defend our comps by (the end of) December. Which of us has a better chance of doing so is a matter for any departmental betting pools. What I do know is that

1) Last year's defenses were all late (I think ranging March-April after the deadline)
and
2) I assured my advisor additional teaching responsibilities would not delay my comps, so I must stick to the deadline.

This puts my poor lab mate in a sorry position. She doesn't have to really worry about the deadline, in the way that I do. I haven't checked with her yearmates (all of whom are doing the double-major thing; I'm a bit of an underachieving oddball) to see if they'll defend on time or late, but our advisor's measuring stick is more likely to be me than them. Our advisor is the one who will probably care, and just think how bad it would look if I defend (less than a year after I proposed my comps) on time and she's late (closer to 2 years after she proposed).

I sort of feel bad about this. My assurance of on-time performance is stressing out a fellow who has been very helpful on assorted matters over the past three years. I don't have much choice on how to progress, however. If I don't manage to defend on time, my advisor will never let me teach again, which would be problematic as I'm seriously considering finding some magical teaching-only position after graduation. So there will be no dance of unspoken agreement that we can both be late defending, taking advantage of those "holidays".

I also feel bad, after reading assorted mother-faculty-challenges posts on ScienceWomen, for hoping that a semester's maternity leave will be as good an excuse for our late defense as an advisor out of the country was for the Master's students'. It's not that I want people to get a negative opinion of childbearing and lactating faculty members' productivity, it's just that it would be so much easier if the deadline were in January.