It is always interesting when people figure that you will always be available to help them when they need your help.
Everyone has a schedule that is their own and what is important is that people realize that there are things that will mean you are not available to assist them immediately. There are times I have had calls from people that figure that I should be able to help them with an issue right away. Of course, I always try and take the call if I can and let them know that I am in the middle of something if that is the cause and will look into the their issue as soon as I can. When I receive email requests I always try to acknowledge them and let people know if there is going to be a delay in getting an answer from me. Issues that are emergencies will get dealt with quickly even if something that is also important has to be delayed for a little bit.
Schedules do change and when you are juggling a number of projects your schedule can really get messed up quickly. Projects that have been sitting quietly can all of a sudden become something that has to be done immediately or a project that has been going full speed can be put on hold.
Having a schedule of what you are going to be working on is important but you have to realize that a simple email or phone call can change your plans. Schedules do help keep me on track when there are multiple projects that are needing my attention. There have been times when I have put a schedule together for working on things one day only to discover that something that wasn't needed has to be completed immediately.
Schedules are very important but everyone has to realize that a schedule has to be flexible otherwise you will go crazy trying to get everything done. There were times when if I had something on a schedule for a given day that I felt it had to be completed that day no matter what I have now come to the conclusion that there will be days when the schedule of things will not get done and i will just have to accept that and deal with it.
When you are working with someone else remember that they also have a schedule. The ability to understand someone's schedule and their demands will help you in understanding your own schedule and how flexible you may have to be.