Using EPPM projects created before the change in accounting principles to ledgers

Our task is scheduled for GoLive successful 2 weeks, and we person decided to power the accounting principles of the ledger according to the contents of this blog(SAP Recommendation: Assignment of Corporate Accoun... - SAP Community).

What I would similar to cognize is whether oregon not the EPPM projects (around 9,000) that were already migrated (before swapping the ledger accounting principle) successful the accumulation strategy can/should not beryllium utilized aft swapping the ledger accounting rule (after transferring implicit customizations).
No transaction information (journal introduction data) has yet been registered successful the accumulation strategy (otherwise it would beryllium intolerable to power the accounting principles of the ledger).
If already registered EPPM projects go unusable, the modulation docket volition request to beryllium importantly revised, which volition person a immense interaction connected GoLive successful 2 weeks.

I would similar to cognize arsenic soon arsenic imaginable whether I tin usage the EPPM task oregon not.
I would beryllium precise grateful if immoderate experts could reply my question.