I read this share buy back as management not understanding why the whole market thinks their farts smell like **** when the management 'team' at Qantas think they smell of roses.
They don't understand that QAN is tarnished with the stain of the current management crop and what they have done decimating, de-investing the actual core business that employs them.
The share price won't rise naturally because no one believes them, of which the market is the best indicator, so they cheat by buying back shares. The cynic in me would think this might have something to do with executive performance plans and share price related bonuses.