It is a fact...not a wish to make it so...but a fact that the crew time was retarded approximately 24 minutes from unaltered April 14th ship's time. It is also a fact that Titanic maintained that unaltered time for the management of routine duties like the compass evolutions Boxhall performed just a minute or so prior to impact on the iceberg. So, both references were in use at the moment Titanic met the iceberg. It baffles me as to why this simple arrangement is so difficult for some people to understand.
The extra time that evening amounted to 47 minutes, split more-or-less evenly between the on-duty Starboard Watch and the Port Watch below. What we know for a fact is that the day/date of April 14th did not end at 12:00 o'clock, but continued on for another 47 minutes to 12:47 o'clock. Halfway between 12:00 and 12:47 had to come the crew's midnight change of watch. As I have said before, I divide that with 24 minutes to the Starboard and 23 minutes of extra duty to the Port. Others reverse the big and little halves, but it's of no consequence. Here's how it worked out in unaltered April 14th hours:
11:54 Seven Bells of Starboard Watch
12:00 Boxhall assisted by Olliver perform 48th compass evolution of April 14
12:04 Impact on iceberg (11:40 crew)
12:09 Wakeup call for Port watch below (1 bell sounded in forecastle)
12:24 Eight bells -- Crew Change of Watch (Bells probably not sounded due to emergency)
12:27 First CQD sent (10:25 NYT)
12:30 Compass evolution by Port Watch
12:47 Becomes 0:00 April 15th -- Change of Day and date
12:30 One Bell of Port Watch
If you note above the ship's bells by which the crew accounted for their Watch and by which they changed Watches was not in synchronization with unaltered April 14th hours at the moment of impact on the iceberg. No matter when it was done, the crew clocks had been adjusted to reflect the need for 8 bells to sound at 12:24 in unaltered time thus signifying the end of the Starboard Watch tour on deck and the beginning of the Port Watch. Let's look at the above chronology, but this time add in crew clock time.
11:54 Unaltered = 11:30 crew time (seven bells)
12:00 " = 11:36 " " Boxhall assisted by Olliver perform 48th compass evolution of April 14
12:04 " = 11:40 " " (Impact on iceberg)
12:09 " = 11:45 " " (wakeup bell in forecastle)
12:24 " = 12:00 " " Change of Watch ("Midnight" for crew)
12:27 " = 12:03 " " First CQD
12:30 " = 12:06 " " Compass evolution by Port Watch (49th of April 14th)
12:47 " = 12:24 " " Change of Watch all clocks reset to April 15th hours
00:00 " = 00:00 " " Beginning day/date/hours April 15th
00:30 " = 00:30 " " Compass evolution by Port Watch
As to time kept by the off-duty junior officers, they had no need of observing crew hours. What they had to do was nip to their cabins for as much sleep as they could get. Don't forget, they worked watch-and-watch. The resetting of clocks on a westward passage robbed them of valuable bunk time. The call to come on duty would come no matter what time they kept on any personal timepiece. And, they had need to keep unaltered April 14th time for their duties during their early minutes on deck. Note the 12:30 compass check (12:06 crew time) was still required under the still-existing unaltered April 14th ship's time. Remember, routinely scheduled ship's business such as those compass comparison evolutions, reading of the log, taking of the air and water temperatures, etc. all took place every half hour.
-- David G. Brown
The WSL Log books were, as were ours, divided horizontally. Each line represented an hour..from 1 o 12 Noon and from 1 to 12 Midnight. The middle of the page was reserved for the Noon up date and included Noon DR and Fix position, Patent Log reading and Course and distance made good. Total clock alteration were noted at Midnight. However that did not mean that the total clock adjustment was made at that time. It simply indicated that a total clock adjustment had been made during the 24 hours covered from Noon on the date of the page on the Log Book until Noon the next day. it did not necessarily mean that for instance that April 14 was 24 hours,47 minutes long. In fact, that calendar day was 24 hours, 24 minutes long. It included one 1 Midnight to 4 am Watch 22 minutes long and one 8 to 12 Watch 8 to 12 Watch which was 4 hours 24 minutes long.
By the same token, if Titanic's course and speed was to be kept the same during April 15 . that Log Book Day would include one Midnight to 4 am which was 4 hours 23 minutes long and one 8 am to Midnight Watch which would have been 4 hours 24 minutes long.