You can still list with InventoryLab and print 30-ups through Amazon Seller Central. We take shipments right up to the point where you can still print your labels.
You will want to turn Automatically Print Label After Submit off in InventoryLab and just list your products.
Go to Your Name (upper right)>Settings>Print Setup
After you create the shipments and send them to your queue from InventoryLab, your next step is to go to your Shipping Que in Seller Central. To get there, log in to Seller Central, then click on Inventory>Manage FBA Shipments:
For each shipment that needs labels, you will want to click the Work on Shipment button to the far right side of the Shipping Que page that displays your pending shipments:
Once you click on the Work on Shipment button, it will take you to the Send/Replenish Inventory page. On this page, click on the Review and Modify Units button. This will display your items from the shipment and allow you to print labels on the 30-Label sheets.
You'll see the MSKU's in the shipment and at the very bottom of the list will be a drop-down box where you can choose the 30-up labels you'd like to print, as well as modify the number of labels for each item if you want to add more items to the shipment.