Update:
I tried the solution you proposed right off the bat, I didnt know exactly if I needed to change anything with my original table or not.
Anyhow starting with my original table: "Table1"
CaseID, TimeStamp, OldTier, NewTier
156, 2010-02-16 11:37, Tier 1, Tier 2
156, 2010-02-16 11:38, Tier...