Creating an anchor in AR UE 4.18 beta 4

I’ve managed to create a scene in which I place an actor in AR using UE. However, I can’t seem to get it to anchor to a point. I believe the issue may be that when I do a hit test, I cannot run ‘hit test at screen position tracking space’ and get it to return ‘existing plane’. When I got this working in 4.17, this was the enum type that was set when the object was anchored (to the AppleARCamera in that case). When I print string the hit tests, they come out as ‘feature point, or estimated horizontal plane’. Also when I promote the hit test anchor to a variable and print string it, there is nothing there (do I need to construct the anchor after a hit test?).

Any help would be appreciated, feel like I am close to being able to do whatever I want, just need anchoring an object to work.