"Vodafone’s CEO ... assured the Home Office that migration to a new platform will provide the necessary fall-back."
Why is it still Vodafone making this assurance instead of some other company?
"The report recommends that the Home Office ensures henceforth that it has guarantees that disaster recovery arrangements are put in place to avoid the failures that plagued the NMAT on the night of the attack."
I'd like to think that the HO realise that disaster recover arrangements aren't actually in place until they've been properly tested and passed. And that they only actually remain in place whilst they continue to pass regular tests. If those conditions aren't met they're not disaster recover arrangements, they're just words. Even more importantly in this situation the prime system is itself a disaster handling system and subject to the same requirements.
Reading through the report it appears that the system had been used for a previous incident in another force and not made ready for re-use.