The MKL V10.3 update 1 is the latest. It is recommended to stay with the latest version to get newest optimization and other improvement. Check "What's new in MKL 10.3" at http://software.intel.com/en-us/articles/whats-new-in-intel-mkl/for more details.
The reason wecontinued to offer bug fixes within V10.2 is toprovide options tocustomers who still need fixesin prior version, see here for reference.
Hope it clarifies.