Foot suggests that the search for Hanratty's Rhyl digs commenced as soon as Hanratty first informed his legal team of his new alibi. Page 220 "Gillbanks left at once for Rhyl." And at p 221 after Hanratty's statement of 29 January, "The information was sent at once to Gillbanks." Also the note of 26 January made by Kleinman or someone in his office refers to Gillbanks being in Rhyl.
The question then becomes when did Hanratty and his legal team in Bedford have the information conveyed to them from Gillbanks in Rhyl? On this Foot and Woffinden disagree. Foot says 7 February and Woffinden 6 February. My hunch would be that Woffinden is right and that Sherrard unleashed the Rhyl alibi on the afternoon of 6 February having had information that there was evidence to substantiate it.