I have a little theory, but I don't know how much weight it would carry with it.
I’m taking into account that the Cave list was printed before, or not incorporating the bookings of Monday 8 April or after. Thus I personally believe that it could have been printed either Monday morning, or at the end of Sunday. This certainly explains why so many passengers who booked within the two days are not on the list. (Ismay's decision to sail was not finalized till Monday, so he is not even on the list).
Of course there were some people who booked before the printing and are not on the list either (the
gamblers, Astors, "Thornes" and the Wicks are those that come to mind).
Anyway, the theory is, Andrews and the other two, part of the H & W guarantee group that were to travel first class were already booked. They however were given complementary tickets, thus priority would be given to paying passengers. Cabins would have been given to these people at the last moment, after the passengers had booked suites and rooms to their likings.
There were other passengers who were not traveling complementary and were not given a cabin (on the Cave list), I think this was so because they simply booked passage on the ship, rather than a particular room, so a specific cabin may not have been allocated to them as yet when the Cave list was printed.
The Queenstown cross channel passengers would have fallen under the same category. Paying only 4 pounds for an overnight trip, their cabins would have been allocated after the New York bound passengers booked the rooms they would occupy for the next 7 days.
Since Titanic was not so heavily booked for its first trip a lot of these passengers I have no doubt got nice cabins. As has been seen Andrews got A36, Fr. Browne A37.
Stead did not get C87 straight away, he would have moved from his original cabin to the larger suite.
Regards,
Daniel.