Unit Price in P4310 - Reg

Hi All,

Appreciate your thoughts on the below Query

1. F41061 unit price is set as $100 with effective date 1st July to 30th July 2016.

2. P4105 cost is set as $125

3. Raised a PO with Order date as 15th July, as expected unit cost defaults as $100 in P4310

4. Print the PO, Cost display as $100.

after few days when I check the PO, unit cost is showing as $125.

When I looked into PO ledger "F43199"  for all the lines Unit cost is shown as $125.

When I looked into Order Revision history, there was no Revision.

Not sure how the cost changes in between?

What would have changed the unit cost (or) what are all the factors that will change the unit cost in P4310.