Defensive matchup

[Rev.Ref63]

Is this rule an unlimited rule? Can a team literally request a defensive matchup "every" time three or more substitutes enter the game?

I worked a girls JH game where the visiting team requested a defensive matchup at the start of all 4 quarters. It just about drove the home team coach crazy. He kept complaining and all I could say was, "It's in the rule book, coach."