The material is used on a station that may or may not be distributed over a particular channel.
In the US, television station refers to a particular provider of content (e.g., WNBC in New York City). It may be distributed over the air, on a particular channel (again, e.g., Channel 4 in NYC), or over the internet, using a particular URL (web address). A given station could provide the same (or different) content over more than one channel.
Channel refers to a particular numerical place on the "dial". At one time, this was a specific frequency over the VHF or UHF spectrum, such as channel 2 (VHF) or channel 83 (UHF). The VHF "channel" were preset (fixed) in TVs analog tuners. The UHF channels were available through a continuous tuning dial.
Once cable became widespread, the channels were delivered over discrete datastreams that were independent of an actual frequency. However, these are still often described by, and accessed using, the channel number that is associated with the channel over which the station traditonally broadcast in that area. But not always.
The OP distributes her services through stations which may use a variety of channels (in the broadest sense) to reach viewers.