you big fault was holding on to a cable box for 1+ year unused that may of dropped off of the system or that you where in area of Chicago land that still had a big analog lineup. I also think that in the past parts of the city of Chicago systems had most of the analog lineup scrambled. But the city of systems where on of the first Comcast systems to go all digital.
Comcast found a way to really rip off most of Chicago land and did some odd stuff. In some areas in the past
TCM is limited basic in some areas and in preferred in others. (not any more)
AS some systems (but not all) in the area have speed in the sports pack. out side of chiagoland land on comcast it is in Analog / digital expanded basic?
some systems had
also is sci-fi in comcast digital preferred / classic. (costs about the same as Direct tv HD DVR) to get hd dvr on comcast add $15-$20/m per box.
out side of chiagoland land on comcast it is in Analog / digital expanded basic. (back in 2007-2009)
the real killer was where they where doing the big analog to digital about half way though it they changed it so you did not get CLTV on the DTA's. But that also meant that you lost most CSN + games unless you got a full SD or better cable box at $6-$8 a TV.
At the same time WOW cable had CSN and CSN + on analog. The DTA where billed as get the same as your old analog lineup. As for why they did not give CSN + SD it's own channle was very odd as the HD one (took over the old MOJO HD for part time needs) that just shows looping help videos. useing cltv for over flow dates back to the old sports channel days.
It get odder later on as when CLTV added an HD feed RCN seemed to put in there CSN + HD slot (they also have both an CLTV SD and an CSN + SD slot).
Comcast did not add the HD feed of CLTV or spilt off CSN + to it's own channel. (other then a few events / games that have been on CN101)
also other systems that did not have CLTV even doing the time CLTV was Comcast only still had ALL CSN feeds. There was even an time where both att-uverse and directv had 3 live HD feeds of CSN CHI (there where 3 live games on at the same time) but Comcast only had 2 in HD.