The ATMS calibration/geolocation software has a requirement of cross granule information in order to properly execute, therefore the first and last granule of a pass cannot be processed. Section 5.2 of the CSPP Installation Guide states:
"For a given contiguous sequence of N raw data record (RDR) processing granules, the user can expect up to N-2 SDR granules, also of 12 scan-lines, will be produced. The first 12 scan-line processing granule and the last 12 scan-line processing granules are used for context and are not processed by the SDR algorithm. This yield may be reduced if there are incomplete intermediate granules."
If you have not done so, please apply CSPP SDR Pathes 3.1.1 and 3.1.2 to your CSPP SDR 3.1 installation. This may help improve the CSPP SDR granule yields by relaxing the filtering of space diary and science RDRs.
In order to get valid data for the first 2 granules or last two granules in your data set, you will need to order one or more RDRs from before the time of the data you are interested in, and one or more RDRs after the time of the data that you are interested. The cross granule requirement for calibration means that you need at least 3 granules in a row to get one valid calibrated/geolocated output granule (the middle granule of the three).