Here are the key dates of the recent GM tenures. I'll leave it to someone else to fill in the transactions for the timespans of interest:
2005/08/11
Rob Katz promoted to Ticats interim General Manager
[url=http://www.cbc.ca/canada/montreal/story/2006/08/29/katz-ticats.html]http://www.cbc.ca/canada/montreal/story ... icats.html[/url]
2006/08/23
Riders announce Eric Tillman as General Manager (note the unfortunate headline)
[url=http://www.canada.com/reginaleaderpost/news/story.html?id=3d3a8850-c5bd-436d-9bee-f72b112fd4e4]http://www.canada.com/reginaleaderpost/ ... 2b112fd4e4[/url]
2006/08/29
Ticats announce Marcel Desjardins as General Manager
[url=http://www.cbc.ca/canada/montreal/story/2006/08/29/katz-ticats.html]http://www.cbc.ca/canada/montreal/story ... icats.html[/url]
"Katz made one last move Monday, trading defensive lineman Adriano Belli to Montreal for defensive lineman Clinton Wayne and defensive back Phillip Gauthier."
[period of infamy begins]
[period of infamy ends]
2007/12/05
Ticats announce Bob O'Billovich as General Manager
[first period of Tillman/O'Billovich overlap begins]
[first period of Tillman/O'Billovich overlap supposedly ends??? (see below re: Tillman's role while on leave]
2009/02/03
National post reports Tillman charged
[url=http://www.nationalpost.com/related/topics/Riders+charged+with+sexual+assault/1248682/story.html]http://www.nationalpost.com/related/top ... story.html[/url]
"Tillman remains GM, but is on leave with pay"
[first period of Tillman/O'Billovich overlap DEFINITELY ends]
2010/01/06
Tillman officially resigns as Riders GM
[url=http://www.cbc.ca/sports/football/story/2010/01/08/sk-tillman-riders-future-100108.html]http://www.cbc.ca/sports/football/story ... 00108.html[/url]
"He had been on paid administrative leave from the CFL club since he was charged last February. However, he worked behind the scenes from his home throughout the season."
2010/09/14
Esks announce Tillman as General Manager
[url=http://esks.com/article/eskimos-announce-tillman-as-general-manager]http://esks.com/article/eskimos-announc ... al-manager[/url]
[second period of Tillman/O'Billovich overlap begins]