Modifying the existing LDA

I am changing an existing filler field in a LDA.
i.e., introducing a new field by reducing the existing filler field. Please see below example

2 #A (a5)
2 #B (a10)
2 #filler (a9)
2 #D (a20)

is being modified to
2 #A (a5)
2 #B (a10)
2 #C (a3)
2 #filler (a6)
2 #D (a20)

This LDA is being used as PDA in few programs, but the new variable #C is not used.
Do we need to STOW all the impacted modules or STOW only the modules which uses new variable #C.

Is #filler ever actually used in any modules? I have seen programs where such fields were used as temporary holding fields. This could cause a problem if an existing object were to store data in #filler, thereby destroying permanent data in #C.

Thanks Steve.
This #filler is not used anywhere in the library.

You will need to STOW all the impacted modules as the CALLNAT is positional and done at the elementary data element level. Where you were passing 4 fields before, now you are passing 5, so all programs using this LDA will need to be reSTOWed.

Exception is if the 4 fields are REDEFINEs already, it which case only the base field for the REDEFINE is actually passed.