Fading Level In When Streaming

Hi all,

I am building a location where I expose new parts of it as the player discovers new areas. I am streaming sub levels that contain lighting information as I expose these new areas of the location. This is to prevent light leaking through false walls etc. What I find is that the lights pop in when I stream the new levels in (obvs). I am wondering if there is a way to fade the level in as opposed to having it just pop in. Because of memory constraints I don’t want to use the sequencer to just expose the levels as required (because doing it this way means they’re always loaded in memory).