Synchronised Red Wattle Birds

For the past few years we have noticed an interesting behaviour of 2 red wattle birds in our back yard. They fly in unison from the back fence and land at the same time on the railing of our balcony. Then they squawk at each other turn around and fly off at exactly the same time and land again on back fence at exactly the same time. They can repeat this for up to 1/2 an hour at a time. If one accidently takes off before the other, it quickly returns, squawks and then they leave together. Has anybody else seen this behaviour and does anybody have any idea what it is all about? We thought maybe flight training for young but perhaps they are practicing for a synchronised flying competition. It is great fun to watch and they look like they are having a super time.
Cheers Leslie