Zortman took over for Bill Kerr, who resigned before the 2010 season to take the Susquehannock job. The Trojans were 2-8 last season.
Suburban athletic director Rich Petersen said part of those original plans have changed, but Zortman will remain with the program in some capacity.
"This plan was put in place to accommodate a head coach candidate who would not be available on a full time basis until the 2011 season," Petersen said in a news release from the school.
"Unfortunately, the candidate for the position in 2011 informed us in December that he would not be taking the position for 2011. After discussing the situation, we have decided to open the head coaching position."
Petersen said Zortman volunteered to be the head coach in 2010 because of his commitment to the Trojans' program, but he had no intentions of assuming the head job for this upcoming season.
"(Zortman) stepped into a very difficult situation and performed admirably," Petersen said.
The York Suburban athletic office is accepting applications through Jan. 17 and hopes to have a replacement in place as soon as possible.