adjusting handicaps
There are two entities that can change a player's handicap - the club's Handicap Committee, and a Committee in charge of a Competition - but they have different powers.
A club Handicap Committee has the ultimate power over a handicap, and can modify the Handicap Index of a member either upward or downward, depending on the findings of a Handicap Review, and / or by discussing reasons of illness or injury or other extenuating issues with the member. The adjustment, or modification, can be set in GHIN with an expiration date or the player can "play out" of the modification naturally due subsequent scores posted.
A Competition Committee can adjust only a Course Handicap of a competitor if they deem it necessary for fair play for an event or series of events. This adjustment is not put into the player's GHIN record. To clarify, the Competition Committee must first convert the player's Index to a Course Handicap then either add or subtract strokes depending on circumstances.