You need to make regular structural changes to a deployed model (for example, weekly changes to the switchover date). You can make these changes by setting revision tags in the development model. However, you also have a development cycle that spans the structural changes.
Let's start with what you don't want to do —take the model out of deployed mode, lose all the development work you have been doing, or synchronize partially developed changes. Don’t worry! Manage these things by following the procedure below.
The following diagram illustrates the procedure (for switchover):
It’s all about planning ahead.
Remember to give enough breathing space to allow for the normal development activities and probably allow for a couple more—just in case.