CCZ's are de-activated for ships entering port or, as in the case of the IOW, anchoring as the harbour is not deep enough to accept the vessel (US Carriers not our little flat deck canoes). The only time that they may be active is when flying operations are taking place whilst 'alongside'. As this requires diplomatic clearance, manning issues, performance issues (no wind over/down the deck) etc. etc. etc. it is rarely done.
Hence, when a ship/carrier is in port or anchored you will not see a NOTAM as the zone doesn't exist. They may get pi$$y if you fly too close but as you are not hampering their operations they don't have alot of choice.
Most military vessels will have lower ROE (Rules of Engagement) whilst transiting 'friendly' waters. They will give far greater latitude than when in a 'hot zone' where the ROE is considerably tighter. But then you wouldn't want to be buzzing around in your little C-150 there anyway.