Amazon RDS Read Replica in Same Region, Different VPC

For version cut-over, I am using CloudFormation to spin up a new infrastructure with a new VPC, Subnets, and Security Groups. I want a copy of my production database in the new VPC (same region). I do not want to use a Snapshot, because that would require me to take the app down for a while (after the snapshot is taken, any new data will be lost, so I have to shut down the app). I want to create a read-replica into the new VPC/SecurityGroup/Subnets, and then when I am ready for cut-over I will promote that read replica. Is this possible? AWS documentation gives clues that creating a read replica across VPCs in the same region is not supported, but does not explicitly say so. Alternately, I am open to moving the database after promotion. Thanks P.S. example of what I mean by "clue": "Within a region, all cross-region replicas created from the same source DB instance must either be in the same Amazon VPC or be outside of a VPC." http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html This almost answers my question... But what about replicas created in the same region as the source DB?