Temporal AA + SSR rendertarget capture issue

I’m having trouble combining TAA and SSR (in UE4.18)
Is there any information around on when the TAA and SSR capture the rendertarget?

I have a 3D HUD in world space (because VR).
With FXAA and SSR, the HUD render correctly but the SSR has a significant lag when the camera moves.
With TAA and SSR, the HUD reflects incorrectly in the floor but the SSR lag is fixed.

Do we have any control of the capture timing, OR a way to render the 3D HUD elements after postprocessing?