All -
Reason for the detour was due to the Mississippi River flooding at Savanna in the late Spring, of 1965. Suspect this is a combined eastbound NCL (#26), EB (#32) and the Morning TCZ (#22) that got on the CGW at Galena Junction, IL (East Cabin, IL was IC) and most likely proceeded east on the CGW to Holcomb, IL where they went through the interchange track, onto home road trackage of the11th Subdivision (Rockford branch). Nine miles south (TT "east") they could return to the 3rd Subdivision (C&I) at Flag Center and "resume" their regular stops at Rochelle, Aurora and Chicago. Only two regular stops would have been "missed" with this detour; Savanna, IL and Oregon, IL. Recall 4960 being used in April, 1965 to move trains through "submerged" trackage at Savanna (see Flickr file, for photo).
Other flood detours went Flag Center - Rockford and then IC thru Galena, Portage and East Cabin back to the Q.
I spent the summer of 1965 as a vacation "relief" operator at the "temporary" control point of East Winona, WI where the Alco rich Green Bay & Western crossed.
Any photos of the Burlington detours passing thru the CGW's Winston Tunnel, not far from Galena Junction?
Bob Campbell