Terrain following on specific waypoints

Hi,
First of all, thanks for the amazing work !
I've been playing around with the arducopter 3.4 beta and the latest version of mission planner. There is this great new feature of terrain following, but it only applies to the entire mission.
Is there a way to have the terrain following activated only on specific waypoints (those close to ground) and not others (those high in the sky) ?

What I need to do is plan a mission where a drone flies some distance above 50 m where just the baro is enough,but then I would likea waypoint at 2 m above ground and would like the drone to use the sonar to be sure it doesn't crash.

Is there any way to implement that through mission planner ?

Thanks a lot for the help and good luck.

The issue names Mission Planner and terrain-following missions but provides no files, tests, or entry points. Start by tracing how mission-wide terrain following and waypoint altitude settings are represented in Mission Planner. Done would require a decided per-waypoint behavior for terrain following and sonar use, plus a documented way to configure and verify it.

Written by the indexing model from the issue text.