The delighted Latics manager believes it is high time more teams joined the 92 and says the standard of the National League is getting better all the time.
He felt for the Southend players and their manager Kevin Maher, who were left stunned by Oldham’s extra-time turn around.
It was the Mellon’s third promotion to the EFL as a manager as he equalled John Still's record.
He says it doesn’t get any easier and knows the time is right to open up the conversation about three teams going up every season.
In February, all 72 clubs in the National League today took the unprecedented step of supporting a letter to the Football League Board requesting a vote to create three promotion places into their league.
Now Mellon said: “Because it's so raw, you'd have to say it's an unbelievable achievement to turn it around and get a result from where we were.
“This clubs is a monster, we were under a lot of pressure to go up because we have a great family behind us that wanted to go up.
“In football you'll always get a chance, you'll always believe you'll get a chance and you have to take it.
“You've got to give these teams in the National League a chance, because there's some big teams.
“I think the EFL has to help the original teams, the EFL has to change. I think the top two should go automatic and the rest fight out, that's the fairest thing for football.”
He added: "It makes so much difference to everything about Oldham as a football club, we can really build forward behind the scenes now.”
Read more about the 3UP campaign here.