GREAT was a heterodyne array receiver that flew on board the SOFIA observatory from early science flights in 2011 until the close of the mission in 2022. In this work we discuss the SOFIA/GREAT post operation activities, such as: i) Support for the Astronomical Community, ii) maintenance of the GREAT data archive, iii) preparation of special datasets: OI data and atmospheric spectra, iv) GREAT data reduction pipeline, v) quality flags: comparison between theoretical radiometer RMS noise and real noise in the spectra, radio frequency interference (RFI), the presence of standing waves, assessment of the baseline quality and assessment of the quality of the atmospheric fit.