Journal Approval- How to create a separate approval flow for backdated journal with a grace period?

Hello all,

I'm trying to create a separate journal approval flow for a specific entity. All journals posted after the month end (i.e., May-24) but within the first 6 days of the next month (i.e., June-24) would be routed for standard 1 layer of approval. All journal posted afterwards (starting from the 7th of June) will be routed for 2 layers of approval.

Can someone please guide us on how to define this rule?

Thank you