Hmm, I think your supply will not be affected. However, you may feel a little uncomfortable during the night there as this is when you nurse but I don't think it will be more than a day or so. Human breast is an amazing thing, it can produce as much milk as is needed and at the time it is needed. I haven't been in your situation but I would assume your body will understand the difference and will switch to a new time. The only problem you may have is putting your dd to sleep at different time but she should be able to adjust pretty soon to new time. You will be fine!