I believe Monarch used to offer a full programme of flights for Renaissance Cruises routing;
The aircraft used was G-MONE in full Renaissance livery
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Photo © Michael F. McLaughlin
I believe Monarch are no longer operating a full Renaissance programme, but are operating some limited services on their behalf.
It is Air 2000 that operate the 2 all-First Class 757s on the air cruise programmes for TCS Expeditions during the winter seasons.
Both Air 2000 and Monarch base 757s in Argentina during the winter operating flights on behalf of Dinar.