Hi,
like I understand from the Microsoft site - http://www.microsoft.com/learning/en/us/exam.aspx?ID=70-523 - you will also get the 'MCTS: .NET Framework 4, Data
Access'.
When you pass Exam 70-523: Upgrade: Transition your MCPD .NET Framework 3.5 Web Developer Skills to MCPD
.NET Framework 4 Web Developer, you complete the requirements for the following certification(s):
MCTS: .NET Framework 4, Web Applications
MCTS: .NET Framework 4, Service Communication Applications
MCTS: .NET Framework 4, Data Access
MCPD: Web Developer 4
So there shouldn't be a problem to get the MCPD Windows Phone (without the need to take 70-516).
Best Regards. Please Mark Answered, If my solution solves your problem.