Barry has been Reserve-team boss for a number of seasons in which he has built a competitive squad at Mid Wales League (South) level - the side finished fifth in the season just gone in what was arguably one of the most competitive campaigns at that level for a number of years.
He will continue to be assisted by Phil Parker who has been his 'number two' with the Reserves.
Presteigne chairman Alan Randell said the committee had unanimously felt it was right Barry and Phil should be given a chance to prove what they can do at the higher level.
"We considered all the options open to us and it was felt this was by far in a way the best route to go down and there is a lot to be said for 'keeping it local'," he said.
"We are grateful to those who expressed an interest in the job but the general view was that Barry and Phil deserve their opportunity to take a side into the Spar League for next season.
"This decision means that we shall be running two senior sides and the Under 18s next season - Presteigne St Andrews will play in the Spar Mid Wales League first division while Presteigne Reserves will play in the Mid Wales League (South).
"Andy Crowe will run the Reserves in the 'South' and we shall not be fielding a CP Llanandras side next season."