George Parris has been appointed Whitehawk manager from next season.
The former Albion midfielder replaces Russel Bromage, who is being relieved of his duties at East Brighton Park.
Bromage was informed of the decision on Tuesday but is expected to remain in charge for the last three games of the season.
Hawks, who are likely to finish runners-up in the County League, appointed Bromage in succession to Ian Chapman last summer and the former Seagulls defender says he is disappointed about how he found out about the news.
Bromage said: "I spoke to the chairman at training on Tuesday and said I needed to talk about next season. It was then he told me they had appointed George Parris as manager.
"It was disappointing to find out another manager knew about it before me. If I hadn't asked about it on Tuesday when would I have been told?
"It is no good being bitter because it won't change matters but I am disappointed how it has been done."
Chairman Wally Sweetman denied the situation had been handled badly. He said vice-chairman Peter McDonnell was getting more involved in the running of the club next season and wanted Parris as manager.
Sweetman said: "We were not disappointed with Russel but Ned (McDonnell) wanted to get more involved and felt appointed George was a good thing to take the club forward."
Parris had already been appointed commercial manager at the club a fortnight ago.
Sweetman revealed the club have ambitious plans for the future but he played down rumours linking Hawks with Kerry Mayo, Guy Butters and Gary Hart should they not be offered new contracts by Albion.
He added: "Ned knows a lot of the Brighton players. He has big ideas for Whitehawk and he said to them if they don't get new contracts and they don't fancy anything else then to come and play for us. It was no more than that."