Impact of non-renewal of SKU

Summary:

If we have a SKU that is implemented and in-use today, during the time of subscription renewal if that SKU is non-renewed, what would be the impact for existing data/information related to that SKU. Will access to SKU still exists for extended period of time except that net new entries/modifications are not allowed i.e., read only (or) do we lose access and all information related to that SKU which breaks our reporting and processes.

For example, Products and Financials today that are tightly integrated using Item. If Products is not renewed, what will happen to existing ACI customer invoices and reports. If we need to reprint an invoice that is 2/3 years old that has item on it, is that even possible?