Snap Shot Account Balance Report

We would like to request that the Account Balance report be enhanced to allow us to run a point in tie A/R and WIP Balance. There are no formatting changes to the report in this request.
When I run the Account Balance report for 5/31/15 at a later date, the report should show the open WIP and A/R as of 5/31/15. I outlined a few scenarios below:
If on 6/1/15 I issue an invoice for time booked prior in May, the WIP balance should not change for 5/31
But if I run the report for 6/1/15, I would see a balance change
If on 6/1/15 I apply a payment to an invoice issued prior to May, the AR balance should not change for 5/31.
But if I run the report for 6/1/15, I would see a balance change
If on 6/1/15 I issue an invoice with an invoice date of 5/15/15, I would expect the WIP balance to change for 5/31
If on 6/1/15 I apply a payment with a payment date of 5/15/15, I would expect the AR balance to change for 5/31
Please also refer to Request #45946 for prior correspondence I have had with support on this issue.

Support has indicated that the date the time is billed is not stored in the system. From my perspective, this is a major problem for a time and billing system. How can I possibly reconcile my WIP every month for financial reported purposes?