It began on 23rd March 2017 and ended on 25th May 2017.
All episodes in this arc can be found here and all images pertaining to this arc can be found here.
The True Colours Arc centers around John coping with losing all communication with Seraphina and being a victim of constant bullying by other students. Subsequently, he begins to reveal the black behind his facade of white: his true colors.
As Arlo's investigation of John's past and his plan to expose the supposed "school cripple" escalates, he comes head-to-head with Isen when the latter tries to end their plans, fearful of what John might do if he is exposed.