Bug 1304642 – comm-central needs to be built with VS2015u3 has become FIXED (many thanks to Edmund Wong), here  you can download the results 🙂

File	seamonkey-2.49a1.en-US.win32.checksums	7K	23-Sep-2016 08:40
File	seamonkey-2.49a1.en-US.win32.common.tests.zip	16M	23-Sep-2016 08:39
File	seamonkey-2.49a1.en-US.win32.complete.mar	43M	23-Sep-2016 08:39
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File	seamonkey-2.49a1.en-US.win32.mochitest.tests.zip	68M	23-Sep-2016 08:39
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File	seamonkey-2.49a1.en-US.win32_info.txt	23	23-Sep-2016 08:40

Only for testing, you will use those builds on your own risk. I recommend to create a backup of your user profile before you start testing those builds.