Joint winner with amateur Sam Bairstow of the 36-hole Final Qualifying competition at St Annes Old on June 28, when he teed off with 1985 Champion Sandy Lyle.
Armitage had back-to-back rounds of 68 to finish eight under par.
He made the halfway cut at Sandwich last year after qualifying through the 2020 South African Open, a closing 15-foot putt giving him the last of three places on offer.
At the time his world ranking stood at 1,398th, but last June won the Porsche European Open on the DP World Tour and climbed all the way to 121st.
His first Open start at Carnoustie in 2018 came after he shared second spot in the Final Qualifying competition at St Annes.
Then dislocated his shoulder indoor sky-diving – it was a birthday present from his fiancée - but played The Open less than two weeks later despite being told it might take months to heal.
After three wins on the EuroPro Tour he also tasted success on the Challenge Tour and made headlines at the Omega Dubai Desert Classic after he was photographed asking Tiger Woods for an autograph on the driving range.