@Kishor Seelan Thank you for posting your question on Microsoft Q&A platform. Happy to help!
From the tile of the question, I understand that you want to know the pricing for Azure Migrate service. From Azure Migrate perspective it is exactly as what you have mentioned. If you keep replicating the VM (not migrated) after the 180 days, we will start charging 25$ for each. Once the VM is Migrated, it is a working VM in Azure so expect the "normal" charges based on the VM SKU and storage.
Refer to Azure Migrate pricing page - https://azure.microsoft.com/en-in/pricing/details/azure-migrate/
Hope this answers your question. Please write back to us if you have any further questions in this matter!
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