Delayed appointments can be very beneficial if they give you time to get to know the Member's staff. Meeting with staff can be as productive as seeing the Member personally. When visiting as a group, one person should start the meeting and be the spokesperson. Before the meeting, decide the key points that should be covered, and who will raise which points. Stick to the issues, facts and don't outstay your welcome.
Congressional offices are friendly places, but they are also places of intensive activity.
Ask for favorable consideration of your position, thus seeking the Member's opinion. When you get home, write a thank you letter to your Member of Congress and any staff with whom you may have met, and ask them to keep in touch with you on your issues.