In modernish police stations apart from interview rooms in cell areas there will interview rooms close to the public entrance. Each woman in a separate room and, because it's a police station told not to leave. The ;last thing you want are civilians wandering around.
1am could well be busy but it's also the time when the night crew will begin their meal breaks which may be covered by those officers going off duty at 2am. Of course circumstances such as shortages of officers might mean delays.
Scribes? No. Interviews conducted by experienced officers, possibly CID. Unlikely to be above the rank of constable. From which statements will be taken. The preamble to a witness statement is covered by the Perjury Act 1911 and the Criminal Law Act of 1967 - or at least it was in my time. This is to get across the seriousness of not telling the truth. Statements are signed immediately below the last line to prevent unauthorised amendments.
A defendant has the right to write their own statement.
How long would they be there?
As long as it takes. And in case you were wondering they will not be provided with copies.
I hope this helps.