It's unclear because the second paragraph is about why the replacement is compatible with pgAgent, literally, "The reason for..." - not that it is a replacement

It's unclear because the second paragraph is about why the replacement is compatible with pgAgent, literally, "The reason for..." - not that it is a replacement. It could also be a replacement for something else that runs on top of pgAgent, or something else that doesn't, and one of the features is that this is compatible. Does that make sense?