Why is Scheduled Ship Date getting updated on the the Backlog Analysis page after Plan Release?

Hello,

We are facing a situation in Backlog Management where the Scheduled Date and Scheduled Ship Date of an order line is getting updated to the Planned Date on the Backlog Analysis page after the Plan results are released. The update is happening automatically without the collection being run. Expectation is that the dates should only get updated on the SO Line after the release and the prior Scheduled Ship Date should not change on the Backlog Analysis page until the collection is run.

Kindly assist.

Thanks