What criteria should be used when creating an inspection lot to determine the inspection lot's start and finish dates, how those dates will be calculated, and how the start and end dates will be updated to reflect holiday calculations?
1) Avg. insp duration should be a subset value < GR processing time that is on the QM plant view page.
2) The insp. lot start date depends on the inspection type.
Unless otherwise specified the start date is = to the insp. lot creation date.
For 04 inspection lots using early lot creation the insp. lot start date is the planned GR date in the order. For manually created lots, including 07 and 89,the start date is specified by the user.
3) The insp lot end date is always the inspection lot start date plus the average insp. duration for the inspection type defined in the material master.
4) SAP does not consider any factory calendar in the calculation of the inspection lot start or end date. Very frustrating if you have QC labs that only work 5 days a week but a plant that runs 7 days a week. If you want to use a special calendar, you need to use a user exit at lot creation to select the proper calendar and perform the calculation.
you need to maintain average inspection time information in material master per inspection type:
From the documentation: "When an inspection lot is created and you enter the start date for an inspection, the system uses the value stored in this field for the average inspection duration to calculate the end date for the inspection. If you enter the end date of the inspection when the inspection lot is created, the system calculates the start date of the inspection using the average inspection duration entered in this field."