I’d separate an obvious tactical problem from an uncomfortable first 20 minutes.
If the opposition are consistently creating the same overload or your full-back is repeatedly isolated, waiting until the hour mark because substitutions feel precious can cost you the game.
But the first change does not always have to be a substitution.
Can you adjust the winger’s position, change who presses, move one midfielder five yards, or switch two players already on the pitch? I would try the lowest-cost solution first.
Before the game, know what your bench can actually change. One substitute might give you pace, another physical presence, another calm possession. That makes the timing easier.
Limited subs require more patience, but not paralysis.
If the problem is clear and the tactical adjustment on the pitch has failed, I would rather make a purposeful early change than save every substitute for a future problem that may never arrive.
