UOM Conversion on Purchase Order Line

Hello Experts,

Does Changing UOM on PO line created using Autocreate . reclacluate Quantity also?

Below is scenario..

Item 'ABC' is setup with primary UOM as Each.. However supplier will accept Purchase Orders in Case only..    ex: (30 each=1 case) .  Both of UOM are under same class.. So changing UOM shouldn't be a problem

Purchase Req is created with 30 each and we would like to change UOM on PO created through Autocreate..

When UOM Is changed it converts price.. However the Quantity conversion doesnt happen automatically? If yes which setup will help this..

Many thanks,

Satheesh