In my time at sea, you didn't only call in at the Marconi depot when you were joining a ship but if you wanted to collect your pay and a travel warrant after signing off, you had no other alternative. When I joined the company at Liverpool that system of calling you in from the R/O's waiting room was definitely in use.
On my first day there I witnessed an almighty row when an intransigent R/O ignored repeated Morse calls made over the loudspeaker on the wall. Eventually the door was opened and the cashier came in and asked the only other occupant why he had not responded to the call. He replied that he resented being treated that way, the callsign was of a ship over in Birkenhead, from which he'd signed off earlier that day and with which he had no connection whatever. He was a person, had a name and would not accept being addressed in any other way.
That's when it all took off. Having only just signed up and accepted my job, I wondered what I was getting into.