MCST is dedicated to the production of a high quality MODIS calibration product. This product is a precursor to every geophysical science product. MCST works for the Science Team Leader and is responsible for developing and maintaining the calibration product (L1B algorithm).
Terra MODIS Collection 6 Level 1B products will be reprocessed to correct for the long term drift observed in the reflectance trending of band 5. More details regarding the reprocessing schedule can be found here: http://ladsweb.nascom.nasa.gov/news/news080414.html
Also, information regarding this calibration change can be found here.