Per the Clan Honor Interpretation Table on Total Warfare p. 274, during the "Post-Invasion" period after 3052, Clan Coyote generally followed strict interpretations of Clan honor. Wars of Reaving downgrades this to opportunistic during the "Pre-Reaving" period prior to 3070 in its own Clan Honor Interpretation table on p. 239.
Assuming for the moment that I'm not missing an interim CHI table (and of course recognizing that every Coyote didn't just wake up one morning and say, "well, we don't have to be all that honorable, right?"), around what year between '52 and '70 would the shift in attitude among the Coyotes have warranted a change in Clan Honor Interpretation?