Fleet tanker and carrier-strike tanker roles in MARS

How would the MARS programme's five planned fleet tankers have differed from its one carrier-strike replenishment tanker?

The likely distinction was less fuel capacity in exchange for enough speed to accompany the carrier group.

The carrier-strike replenishment tanker was thought to trade some fuel capacity for speed. It would need to remain with a carrier group during fast combat manoeuvres, while ordinary fleet tankers stayed with the replenishment group. The Falklands task-force structure provides the comparison: carrier, amphibious, and replenishment groups exchanged ships and stores. A faster tanker might also refill from the slower tankers before returning to the carrier group.