According to the Archiving Report the alarm was raised around 10pm, some people choose to interpret around 10pm to be anything from 9.30pm to 10.15pm in order to make their theories work, however in my book around 10pm means 9.55 - 10.05pm - how do you choose to interpret it?
Sorry mods wandering off topic here! bin it if you like!
The report says around 22:00?.
I wouldn't try to second guess the accuracy they implied with "around" until I had read what they had read by way of testimony.
The statements of those involved seem to give a "start time" as early as 21:45 and "finish time" as late as 22:00 for the alarm being raised. Of course you can play interpolating games if you wish with times in other statements and how long does it take to have a pee or eat a piece of steak to shave a few seconds off here or add a minute on there if you wish.
I am happy with 21:45 to 22:00.
Then we have the Smith's statement to fix a time on. Mr Smith seems to think they left Kelly's bar 21:50 to 22:00
So a potential sighting time can reasonably assessed and it's span.
Then do a little plan based on Earliest Start/Earliest Finish. Latest Start/Latest Finish. Earliest Start/Latest Finish for both events and see what pans out.