Chicago didn't get their first UHF station until 1964 with WCIU.
WCIU didn't go on the air until 1964, but the original CPs for them, WXXW/WYCC, WFLD, and WSNS were issued in the mid '50s.
WXXW (now WYCC) 20 was originally WIND-TV (Ralph Atlass/WIND radio - Westinghouse kept the CP active after they bought WIND in 1956, then sold it to WTTW).
WCIU-TV 26 was originally WHFC-TV (WHFC radio).
WFLD 32 was originally WTLE, assigned to Evanston (Northwestern Television).
WSNS 44 was originally WOPT, assigned to Oak Park (WOPA radio).
None of these stations were ever built by their original owners.
There was also a CP for a WJOL-TV 48 Joliet in 1954, but it also was never built. Channel 38 was originally WCFL-TV, but that CP was assigned sometime in the '60s, but those call letters were used in early 1976, when WCFC began testing but had not received that callsign by that time.
The original UHF allocations for the Chicago metro area were (* means noncommercial allocation):
Aurora: 16 (later 60)
Chicago: 20, 26, 32, 38, 44 (no changes except to make 20 noncommercial)
Gary, IN: 50, *66 (later *50, 56, finally 50, *56)
Hammond, IN: 56 (later 62)
Elgin: 28 (later 66, reassigned to Joliet)
Joliet: 48 (later 14, finally 66)
Kankakee: 14 (later *54)
Michigan City, IN: 62 (withdrawn - 62 reassigned to Hammond.)
Waukegan: 22 (withdrawn