come to vs get on to

come to

verb
  • Used other than figuratively or idiomatically: see come, to. 

  • To total; to amount to. 

  • To devote attention to in due course; to come around to. 

  • To stop a sailing vessel, especially by turning into the wind. See also come about. 

  • To reach; to arrive at. 

  • To befall; to happen to; to come upon. 

  • To seek help from. 

  • To recover consciousness after fainting etc. 

  • To regard or specifically pertain to. 

get on to

verb
  • Used other than figuratively or idiomatically: see get on, to. 

  • To contact (someone) in order to raise or discuss a certain matter. 

  • To progress to; to start working on. 

How often have the words come to and get on to occurred in a corpus of books? (source: Google Ngram Viewer )