^MCN keeps the bitmap, so this label prints behind the next one. The preview draws every label clean and warns on ^MCN.
^MCaThis command is a printer setting: the preview recognises it and skips it, because it does not change how the label looks. Its effect shows on the real printer.
^MCY| Parameter | Description | Type | |
|---|---|---|---|
a | clear the bitmap (Y) or carry it to the next label (N) | enum | Default: Y · Options: Y, N · ignored in preview |
The marked parameters are part of the ZPL specification and work on a real printer; the preview engine ignores them today.