Another time conflict that has come up several times are working my schedule around guests, or being a guest myself. The conflict of having guests is actually two-fold. First is the problem of me being up at night. My wife and I live in a small house, under 800 sf., so when I am up at night, I tend to be out of the bedroom, as it affects her ability to sleep through the night. On the other hand, when we have guests, it is inappropriate for me to be banging around in the living area, since our "guest room" is a nook off the same space. Because the this conflict impinges on the ability of other people to sleep, I have had to resolve it by moving to a monophasic sleep schedule while they are here. In the future this will be resolved when our den/ guest room is finished, so the guest will be in a different space. We have access to a camp down the road, so we have mostly been able to avoid this conflict by having our guest sleep in the camp. This is especially nice as it gives them some personal space as well.
The other issue that comes up with guest is that they are on vacation. My sleep schedule has a nap in the middle of the day. Usually, my afternoon nap coincides somewhat with most people's lunch, so it is not very inconvenient. Even on the weekends, most of my friends are not getting together socially until after about 2pm. However, hanging out with guests who are on vacation, they want to get together for lunch, and then go do something, or at least interact. It is often perceived as rude, or at least ... arrogant to insist on an afternoon nap. When my in-laws were staying up, there was also social pressure not to appear lazy. Even though I was working a full day, and then hanging out with them for several hours every day, the hours that I was awake at night do not count socially. My work around for having guests involves shifting my schedule slightly so that my morning nap happens earlier, and my afternoon nap is taken at around 10:15 instead of 1:30. This allowed me to meet them for lunch and have the afternoon with them. During the week, it was socially reasonable for me to beg off a little early (around 9:00pm) and I would have an early evening nap as well.
So much of timing depends on your social mores. We live in the country, and so there is an expectation of getting up early and going to bed early. I suspect that if you live in the city there is more expectation that you would be staying up later, in which case you may need to imply that you have something pressing that you need to take care of and will meet back up with them in a few hours. It is funny, because all my friends and family know that I sleep triphasically, and only sleep for about 4 hrs total during a 24 hr period, and yet I get some grief any time I try to sleep when they are awake. Social peer pressure is huge and a higher hurdle to adopting a polyphasic lifestyle than many people might think. I wonder how people that work night shifts deal with having guests for extended periods.
