THRIFT UNIT SHUFFLES EXECUTIVES
The troubled Financial Corporation of America said today that its directors had promoted three senior executives to a newly created office of the president, but it added that Charles W. Knapp would continue as chairman and chief executive. The board described the changes as ''very positive,'' but it did not indicate the reasoning behind them. Harvey Rosen, a partner in Rosen, Wachtell & Gilbert, a law firm that specializes in the financial services industry, called the changes ''an effort to stave off the regulators.'' ''But,'' he added, ''I don't think it's going to accomplish that. So long as Knapp appears to have unfettered authority, the regulators are not going to be satisfied.''