To answer yesterday's question, it's 3:35 or 3:34
Yes, "25 or 6 to 4" is a time reference. And it was probably not ACTUALLY intended to answer the question, "Does Anybody Really Know What Time It Is?" although Robert Lamm wrote both of them. From their 2nd album, Chicago, this was a triumph of middle-of-the-night songwriting.
When Peter Cetera left Chicago in the 1980's for a solo career, the band got a new vocalist and decided to remake the song for Chicago 18. It was significantly less horny (but NOT horn-free) and less successful. It was cleanly performed. It just didn't have the same charm.