Rumors have it that 5.0 is slowly rolling out for Sprint Note 3.
The Note 3 is a single band LTE phone. It is not a Spark phone and will never get Spark. If you want spark? You will need to upgrade to Note 4 or S5.
Also, remember all spark phones do not support SVLTE. For that reason, Note 3 will be my last phone on Sprint. I will go to ATT. Unless, Sprint brings back SVLTE.