Yep its an optimised gliding trajectory from the apogee point (ie the max altitude gained after booster burnout). So it is more of a custom algorithm model based trajectory optimisation method that you can implement in various missiles guidance system in OBC, be it surface or air launched for a specific range constraint ie upto 300-400km. Based on this optimisation, your regular vanilla ballistic article can be flown like a hypersonic glide weapon or like mimicking flight path of a very high speed cruise missile across multiple altitude level (and also implement waypoint navigation with other technique) as compared to flying in predictable parabolic/elliptical flight path. Range extension possible as much as 25-30%.
Rudram 2 R3 and other aeroballistic future missiles will also have various programs inbuilt based on this model that will optimise the flight path like that which is absolute nightmare for any AD system to track and lock onto. This technique is more of universal mathematical model that would be implemented for a specific range engagement case. When a missile flies along such optimal trajectory, the max range can be extended without changing general aerodynamic config or addition of extra fuel/motor stages , but rather by prioritising specific control parameters like total flight time, angle of attack, velocity of missile, flight height , flight path angle etc in the program.
Usual method of flight trajectory optimisation technique is either via direct method where mathematical programming like this will make a pure ballistic article fly like a real timecontrollable glide missile. Or via indirect method based on optimal control principle involving two point boundary value solution which is more extensive programming dependent.