What is the best practice for inputting an extension of a lease into the module?

Summary:

What is the best practice for inputting an extension of a lease into the module?  Should it be entered as a separate lease for only the extension period?  Sometimes we know a year before the original termination date that we will be extending. Often the original lease contained a lease incentive or initial direct costs that are being amortized and I would expect should be amortized only over the initial lease term.  If we add the extension period onto the current lease, does that extend the amortization period of the unamortized incentive and costs? If it does, should we not