How eight Type 31 frigates sustain distant stations

How would the rule of three apply to a forward-based Type 31 force?

Eight ships could sustain paired distant deployments while two remain in Britain, with rotating crews reducing the need to bring each hull home.

Eight Type 31 frigates could be divided into pairs for several distant stations while two remain in Britain for deeper maintenance and crew preparation. Hot crewing lets trained personnel fly out to relieve an overseas crew, keeping the ship on station while sailors rotate home.