The concept is that you have to maintain the timing plan for a sufficient period of time ranging from as little as 15 minutes up to the maximum sustained traffic conditions.
The fully adaptive signal keeps changing the timing plan.
I agree with Mr. khaled Al-Sahili. If you are using fully adaptive signal then the idea is to have signal that corresponds exactly with the traffic. But there are some guidelines for this case. Usually a count of 15 minutes is taken as the best measure for flow rate so the max number of signal timing plans can be 4 (15 min) x 24 (hours of day).
If you are using pre-timed signal then there can be 3 plans, one for each morning and evening peak hours, assuming that the direction split would reverse in them and one for off peak hours.
I agree with the above answers. When I did traffic intersection analysis using SIDRA, for planning and design purposes, I used to have 2 plans such as AM peak and PM peak. But, the operational section use signal-timing plans such as AM, Off-peak-in the day, PM, night and week-end plans depending on the traffic volumes.