Mobile offshore drilling unit, a method of using such a unit and a system comprising such a unit

An offshore well-processing system for performing one or more well-processing tasks, the system comprising:

• a mobile offshore drilling unit and a remote well-processing device configured to be mounted on an offshore platform separate from the mobile offshore drilling unit, the mobile offshore drilling unit defining at least one well centre and comprising at least one primary drill rig comprising at least one drill floor and at least one hoisting system for raising and lowering tubular equipment through the at least one well centre from/into a well in the seafloor;
• and
• wherein the remote well-processing device is configured to perform at least a first of the one or more well-processing tasks when mounted on said offshore platform at a position displaced from the at least one well centre defined by the mobile offshore drilling unit;
• and
• wherein the mobile offshore drilling unit and the remote well-processing device are configured to be operationally coupled to each other when the remote well-processing device is mounted on said offshore platform;
• and
• wherein the mobile offshore drilling unit is configured to assist concurrently in two or more of the well-processing tasks performed concurrently on respective wells, including the first well processing task performed by the remote well-processing device on a first well and a second well-processing task concurrently performed by the offshore well-processing system on a second well.