No, downtime is not required for importing and updating new products in Tagrain.

The Serial and Batch Products feature is available in Tagrain on activation of the "Serial and Batch Product Management" plugin. See: Features of the Serial and Batch Product Management Plugin

The Variant and Composite Products feature is available in Tagrain on activation of the "Variant and Composite Product Management" plugin. See: Features of the Variant and Composite Product Management Plugin

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