SSIS 2012 metadata not refreshing on re-deploy
Honestly, you shouldn't be editing the package to point to another environment before deploying it. Please look into package configurations to learn about methods to deploy your packages without editing the package itself.

Likely your connection strings and other settings should just be a variable read from a configuration file.

Since you are using SQL 2012 you should probably be using environments (thanks @MartinSmith)