Since I might be doing a similar thing in the near future, I decided to see if I could push 4-5 small test databases to Azure SQLDB at the same time (SQL on Azure VM test may come later). If this happens with my client it will be hundreds of databases, with the same schema but wildly varying sizes.
Create 5 sample databases
Create .bacpacs on local drive
Create Azure Logical Server if not already done (see step 4)
Create a Notepad of SQLPackage.exe commands, one for each .bacpac
Run with “start” in CMD to fire off separate windows
Worth reading the whole thing.