If drop-in files are passed by command (what could easily happen when you use a tool like find for determining the files), these are prone to false positives of Multiplicity-warnings.
E.g.
ExecStart=
ExecStart=-/bin/foo
would give two false warnings (one for the missing value of the first ExecStart and 2nd of the multiple ExecStart entries).
Fix that by ignoring any drop-ins from command-line (these are parsed automatically anyway)
If drop-in files are passed by command (what could easily happen when you use a tool like find for determining the files), these are prone to false positives of Multiplicity-warnings. E.g.