It has been a busy summer for the 19-year-old, who finished his loan spell at QPR at the end of May before heading off on international duty with the Republic of Ireland under-20 side and was then promoted to the under-21s for their European Championship qualifiers.
He returned to the club last Wednesday and was told to pack his bags for the trip to Spain.
"It's great, I got back and was told I was going to La Manga - so I was absolutely delighted," he beamed. "It is a great boost to come back into pre-season training, get away here and get to know some of the first team players.
"It is my first time away in pre-season, I travelled with the squad last year but have never been away training with them for this long a time. It is good just to get in and get to know the players."
Mingling with the big boys does not faze the confident Kelly, but he does admit to not overplaying it on the inevitable banter-front in the first few days.
"You wouldn't go diving in head first straight away. You take it easy, but it is a good laugh and a good crack.
"It is great here, the weather is something else. You can see why teams come out here - you can relax as well as get the hard work done."
Stephen added that his aim for the season is to be in and around the first team squad in terms of selection and hopes to make a suitable impression during the pre-season campaign.
"It would be nice, but I'll have to see what happens through pre-season. If I get the chance to play in any of the friendlies I'll have to show what I can do.
"It would be great to stay at the club for the season, to start getting in the squad would be really nice. I'll just have to see what happens."
Young defender Stephen Kelly is thrilled to have the opportunity to prepare for the new season with the first team in La Manga.