Per 
This list is currently incomplete.
Omega-7 Period
Two years before Incident Zero: SCP-105 is 13 when the Foundation recruits her.
Currently Unknown (assumed to be nine years before attack on Site-17): Incident Zero. SCP-105 is 15.
Around same time as Incident Zero (presumably): Events of Duke 'til Dawn.
In-Between Period
Unknown Date: Events of The King is Dead.
October 4th, 2014: Dr. Chelsea Elliot is interviewed by Taggart.
Alpha-9 Period
Somewhere between late 2014 and early 2015: Events of Immediate Actions. SCP-105 participates in the defense of Site-17 from unknown hostiles. She is 24.
Three weeks after Immediate Actions: Events of Girls' Night Out.
Anywhere between Jan-Sep of 2015: Aleksander Foxx joins Lambda-2. Calculated from age, DoB, and number of black boxes in his examination report from Tinker, Tailor, Soldier, Huntsman
March 31st, 2015: Dr. Elliot joins Alpha-9.
April 5th, 2015 (presumably): Events of Operation "Camp Granada".
Somewhere between late 2015 and early 2016: Events of No Joke and Iris' portion of Calm.
