Upgrading to cashier version 11

Hi,

Has anyone upgraded to cashier 11 and migrated their existing data to the new multi plan structure? Would it be safe to leave the subscription_items table blank for existing subscriptions?

I'm upgrading a project which is using cashier version 5 and Stripe API version 2015-02-16 and i have a lot of existing data. Do i need to fetch the subscription items (or the latest one probably because the system wasn't used with the multi plan option in mind) for each subscription manually to fill out the data? I would gladly skip this if I can.

Thanks