Old Invoices have no Accounting Dimension

I manage projects by putting accounting dimensions (project, cost center) for each sales invoices and purchase invoices. In old version from v12 down, there is no accounting dimensions at the invoice form, only put them in Item form. However, v13 introduce accounting dimensions in both invoice form and item form, so all old invoices are missing dimensions (projects, cost centre). Unless I have to recreate new invoices, otherwise the invoices will not show up in related projects.
So how can I fix this?