Davidson, who made just five appearances in all competitions for the Baggies after joining the club last August, is on his way back to Melbourne to sort out his club future and have a brief break before going into camp with the Socceroos for next month's 2018 FIFA World Cup qualifier against Kyrgyzstan in Bishkek.
Though he could have remained at the Hawthorns for another 12 months, Davidson's desire to play each week was the driving force in his decision to request a release.
Davidson was pivotal for Australia at January's AFC Asian Cup and starred in the shock 2-2 draw with world champion Germany in Kaiserslautern in March.
At 23, he is hungry for regular club football and was denied that opportunity when West Brom vetoed a loan move to Championship side Reading in January.
His father, Socceroos great Alan Davidson, said the left-back had left Albion on the best of terms with coach Tony Pulis, explaining: "Jason didn't really fit into the system which Pulis has been playing, and wasn't part of his long-term plans and he respects that.
"There's always been a respectful relationship there between the two, and Pulis sees Jason as a good professional.
"To be honest, the club has been fantastic with Jason.
"Pulis has come in and saved them from relegation and you have to give him great credit for that.
"He always worked hard throughout his stay there … putting in extra training on his own to make sure he was ready if the call came from the club and also to be ready for Australia.
"I have the utmost respect for the professionalism of everybody at the club and also the fans who have saying some supportive and positive things and wishing him well on social media."
