As of mid 2020, it seems the date has to be set in 2016, not 2015 (later than 2016 may also work, from other comments). See some further details and steps clearly outlined at this link: https://superuser.com/questions/1495770/upgrade-from-yosemite-to-el-capitan-no-packages-available-for-install-crea
+
As of mid 2020, it seems the date has to be set in 2016 (I used a summer 2016 date), not 2015 (later than 2016 may also work, from other comments). See some further details and steps clearly outlined at this link: https://superuser.com/questions/1495770/upgrade-from-yosemite-to-el-capitan-no-packages-available-for-install-crea
As of mid 2020, it seems the date has to be set in 2016, not 2015 (later than 2016 may also work, from other comments). See some further details and steps clearly outlined at this link: https://superuser.com/questions/1495770/upgrade-from-yosemite-to-el-capitan-no-packages-available-for-install-crea