[9][10][11][14] In 2013, Armstrong received a 2:1 Bachelor of Arts undergraduate degree in English Studies from the University of Stirling[13] and returned there to complete a Master of Letters in Creative Writing, graduating with Merit in 2015.

[18][19] In 2021, Armstrong wrote and starred in a short film for the Edinburgh International Book Festival Infectious Nihilism and Small Metallic Pieces of Hope[20] directed by James Price.

[24] Armstrong wrote and presented a three-part BBC Scotland documentary series, Street Gangs[25][26] exploring current Scottish gang culture, including the recent impact of social media, drill music / roadman culture, and his lived experience as an ex-gang member, which aired in October 2023 and was featured on BBC iPlayer.

[27][28][29] Armstrong is an ambassador for The Hope Collective, a London-based anti-violence organisation, formed originally to support the 20th anniversary legacy campaign for Damilola Taylor.

Later in 2024, Armstrong joined a panel of experts at the Convention of Scottish Local Authorities (COSLA) national conference alongside Karyn McCluskey and Maureen McKenna OBE to discuss early intervention and prevention,[33] where First Minister of Scotland John Swinney also delivered an address.