Qantas website showing flight search to USA with return flights greyed out

[Flying Sailor]

Advise please: Qantas site flight search showing most return flights greyed out with notice not available with this fare type, suggesting I need to book an alternate outbound flight? why is this?

 

[mannej]

What fare type are you trying to purchase?

 

[Flying Sailor]

What fare type are you trying to purchase?

It is a saver fare, (lowest upgradable fare?) flight out 8th Oct, return 31st Oct '14

 

[Flying Sailor]