The Guardian seems to have forgotten about the £10bn contingency:
"The UK’s parliamentary spending watchdog, the public accounts committee, on Friday warned of a £21bn shortfall: in other words, the Ministry of Defence does not have enough money to buy all the equipment it says it needs. It singled out for criticism spending on the four Dreadnoughts."
The ring fencing comment [ that follows the above quote] on finance is correct for the Dreadnoughts but not for the Astutes.
The relevant DG has been, though, tasked with a cost reduction plan (to come up with one, together with the industry), as in:
Who is responsible? [from NAO/ MoD "facts" publication]
the ‘Top Level Budgets’ will deliver the right mix of staff across the whole force.
These comprise the Head Office and Corporate Services; the four Commands;
Defence Infrastructure Organisation; and DG Nuclear
- there has only been a DG Nuclear in post for a year, thereby making it "independently acting"
- whereas the blundering DIO has been reduced to a delivery agency and the Heads of Commands now own the budget as for the accommodation aspects (a recent change, and for a good reason, too)