Different SDK levels for Application and Bootloader

Does it cause issues if the application was built with a different SDK level than the bootloader? I have a project I'm adding a bootloader to, and it isn't working. I have done over a dozen of these, yet I'm at a loss why I can't get this one working. One thing I noted that is different, is that the Application was built using SDK 15.2, while the Bootloader is currently setup to use SDK 15.3. The soft device is S112_v6.1.1.

I can obviously put them at the same level, but since the question has not been asked as far as I could find, I wanted to put the question on the forum for a real answer. This may not even be related to my issue, but I was curious.