The source of the information is attributed to unnamed "industry sources", so we can't say how reliable the information might be. That said, it's not all that hard to believe that March would be a target for Samsung, given that it will more than likely be releasing the Samsung Galaxy S6 that same month. Samsung likes to time most of its big releases for either March or October, so that makes sense.
There were some rumors that Samsung could show off the Gear Blink at this year's IFA, but obviously that didn't happen last week; so, now the rumors have shifted to the next Samsung release window. We'd say take this with a grain of salt, until we get more solid leaks regarding the device.