Hi there,
I am a professional system administrator, very experienced with both Windows Server and Linux.
I can complete this migration for you professionally, and efficiently. I would back up your data before we start, to ensure everything is safe. Then migrate you over the linux server.
Once the Migration is completed, I would then complete the work to move your data from the Elastic Block Store to your S3 bucket, and recode your PHP app so that it is using your S3 bucket.
Please check my profile to read about the quality of my work, everyone I have worked with has given me excellent reviews. Hope to chat soon.
Best,
Gary