They've run out of money and the 'Review' is simply a way of kicking the project into the long grass until money becomes available.
breathtakingly,for those who remember Feb 6, 2016
Type 45 Destroyers:Written question - 67575
Asked on: 13 March 2017
"To ask the Secretary of State for Defence, when he plans to award contracts for the Power Improvement Project for the Type 45 destroyer class."
Answered on: 16 March 2017
"On current plans, we anticipate that the Ministry of Defence will be able to award the contract for the Power Improvement Project for the Type 45 Destroyer class in early 2018."
(related, dated May 2016 though:
Project Napier sees twin-track plan adopted to resolve Type 45 problems
not only Third World (or worse) level of armament, but also late:what a joke of a frigate! scandalous, sending the RN to Bangladesh level (and I don't mean to downplay the Type 056 export-version!)
shame on those compliant to such a "solution" mainly the current Admiralty!