In January 2022, he earned his first IM norm at the Roquetas Open, during which he defeated grandmaster Karthik Venkataraman and drew with grandmaster Daniel Dardha.[1] He finished the event tied for first place with Alexandr Fier, Liam Vrolijk, and Tor Fredrik Kaasen.[2]
In August 2022, he won the British Chess Championship, where he finished a half-point ahead of grandmaster and defending champion Nicholas Pert and also received his first GM norm.[3]
In May 2023, Harry obtained his second GM norm in the 4NCL playing for the Sharks team.[4]
In May 2025, he played on the top board for the Manx Liberty team in the Four Nations Chess League. He was the top scorer, achieving 9.5/11 and helping the team to the championship.[5]