Almighty God, who didst commission thy holy martyr George to bear before the rulers of this world the banner of the cross: Strengthen us in our battles against the great serpent of sin and evil, that we too may attain the crown of eternal life; through Jesus Christ our Redeemer, who livest and reignest with thee and the Holy Spirit, one God, for ever and ever. Amen.
Good heavens! What is “provisional” about the Feast of St. George the Great Martyr? It has been on the church calendar (both East and West) for more than a thousand years.
Evidence beyond tradition, perhaps? The RCs demoted St. Christopher for that reason.
St. George’s existence has been pretty well established and documented, though some details are certainly debatable and there is a lot of pious legend around him. Wikipedia has a good article on him [url=http://en.wikipedia.org/wiki/St._George]here[/url].