It can't be automatically.
Info record is a master data and Purchasing document is just a document for vendor.
System will never update it automatically in standard.
It has discussed many times before.
As per you initial question.
You can achieve this by simple maintain the price date category 5 in info record.
I've tested that and it's working as per your requirement.
I've created a info record with price 70. Then I've created a PO, system picked the price 70 automatically, I've saved the PO. Then in ME12, I've changed the price for info record as 100.
Then I've done Goods receipt. My accounting entry generated for the price 100.
Please test the scenario in your practice client and revert back if any issue.
***Edited by: Dëv Päträ