Which answer is FALSE for adding the $7$th character extension to an ICD$-10$ code?

Initial visit for $S57\mathrm{.}02$ will require the dummy place holder $$f $"x"$ and would be billed as$\_$S$57\mathrm{.}02$XA

Subsequent visit for W$14$ will require two dummy place holders of $"x"$ and would be billed as W$14.$XXD

Sequela visit for T$80\mathrm{.}419$ would not require any placeholders of $"x"$ and would be billed as T$80\mathrm{.}419$S

Subsequent visit for $S54\mathrm{.}90$ will require a dummy place holder of $"x"$ and$-$would be billed $S54\mathrm{.}90xxD$