It’s then up to the agent how they pay the rest, either by paying in Shine points or a mixture of points and cash.
P&O Cruises director of sales Ruth Venn said the line’s travel agent partners have been "so supportive" over the last two years.
"We wanted to give them something truly meaningful in return," she added. "This offer gives agents a fantastic opportunity to enjoy Iona’s fabulous dining, world-class entertainment – and everything in between."