Apart from taking your chance in the queue, you can dial DINE whatever that equates to on the phone (3463?) from your suite & ask to reserve a table. There are only certain times that you can book, but well worth remembering.
have a memorable cruise,
Last Cruise: Royal Princess August 2015
Next: P&O Oriana October 2015
Then: Queen Victoria January 2016
Golden, Grand(2), Caribbean, Royal, Sea(4+1 aborted)
Adonia(4+2), Arcadia, Artemis(2), Aurora(5), Azura(2), Britannia, Oceana(3), Oriana(11), Ventura(2), Victoria(5)
QM2(2), QE2(9), QV(6), QE, Caronia(2), Minerva, Minerva II, Fred.Olsen(8), NCL Jade, =X= Eclipse, HAL Ryndam, Aza.Journey