The ascension refers to the transfer of our Lord’s true humanity from earth to the third heaven in his resurrection body.
His session includes the glorification of His humanity, which is His seat at the right hand of the Father.
His advocacy on behalf of believers (1 John 2:1) – this encompasses the time from the ascension to the second coming of Messiah when his enemies will be made his footstool.
Reference the definition “Hypostatic Union” (Luke 24:30-53; Acts 1:9; Hebrews 12:1,2; 1 John 2:1).