MCAD questions/timeframe

I have a couple of questions regarding MCAD certification. The Microsoft website says the following:

"If you use Exam 70-305 or 70-315 to satisfy the core exam requirement, you may use either Exam 70-306 or 70-316 as an elective.

If you use Exam 70-306 or 70-316 to satisfy the core exam requirement, you may use either Exam 70-305 or 70-315 as an elective."


So, I can take a vb or c# windows forms exam as a core exam and then take the vb or c# web exam to satisfy the elective? And vice versa? I want to make sure its as straight forward as it sounds.

Also, is there a timeframe that they require you to finish the 3 exams. For instance, could I spread it out over a year?

Any help is appreciated.