In one aspect, a method includes (i) receiving query fingerprint data representing content transmitted by a content-distribution system on a channel; (ii) comparing the received query fingerprint data with multiple reference fingerprint data sets, wherein each of the multiple reference fingerprint data sets corresponds with a different respective content segment; (iii) based on the comparing, detecting a respective match between the received query fingerprint data and reference fingerprint data in each of the multiple reference fingerprint data sets; (iv) accessing broadcast-schedule data associated with the channel; (v) using the accessed broadcast-schedule data to identify which one of the different respective content segments is being transmitted by the content-distribution system on the channel, thereby identifying a corresponding upcoming content modification opportunity on the channel; and (vi) performing an action to facilitate performing a content modification operation related to the identified upcoming content-modification opportunity on the channel.