A pre-inquest review into the IRA's Guildford pub bombs has been postponed due to an imminent ruling over the Birmingham bomb attacks.
The Appeal Court is expected to say next week whether the suspected Birmingham bombers can be named.
Surrey Coroner Richard Travers postponed his hearing after lawyers for Surrey Police advised him the ruling would be "potentially relevant".
Lawyers representing a survivor and two families have criticised the move.
A Surrey Police letter to Mr Travers, which has been seen by the BBC, said police lawyers had seen a copy of the draft Birmingham judgement under embargo.
The letter stated: "It is potentially relevant to the hearing on Friday."
Police had suggested the coroner delay his judgement but not the hearing, but Mr Travers said that was not satisfactory.
The Woking hearing was to hear submissions on whether a full inquest into the Guildford deaths should be resumed.
Five people were killed and 65 were injured in explosions at Guildford pubs in 1974, after which 11 people - known as the Guildford Four and Maguire Seven - were wrongly convicted.
Christopher Stanley, from KRW Law, said the coroner's decision to postpone "showed a lack of understanding of the concerns of the families".
He said the family of bomb victim Ann Hamilton were "disappointed" with Mr Travers' decision and his "failure to consult" their lawyers.
"He refers to the Birmingham pub bombings proceedings, but they do not understand how their request to resume the inquest into the death of their sister is related," Mr Stanley said.
"They have been excluded as the victims - as they have been from all previous investigations and inquiries into the Guildford pub bombings."
Had Friday's hearing gone ahead, Mr Travers would have heard a request by KRW Law for the disclosure of more than 700 files that remain closed at The National Archives.
In the past fortnight, three more sets of documents have been released following freedom of information requests.
They contain allegations about the loss of some of the legal files relating to Guildford Four member Gerry Conlon, harsh conditions he was subjected to in prison, and further claims of police ill-treatment in the early stages of the investigation into the bombings.
Mr Travers has proposed relisting the pre-inquest review in December.