[Koha] Koha Upgrate 20.11.15 Version

Hi, We carry out the automation processes of public libraries at the General Directorate of Libraries and Publications in Turkey and use the Koha automation system. This year, the transition from version 3.20 to version 20.11.15 continues. We would like to get your opinion on what we should pay attention to when updating the version. Have a nice day.