We were at WDW 8/2-8/13. The first day we went to Epcot was 8/8 at about 5pm. The park map showed "future site of MS", but we went straight to MS, the FP machines were operating....there wasn't much of a wait in the standby line, but we got a FP and then went to Norway (we noticed that on the MS FP, it showed that we were eligible for another FP in 5 minutes (although it would not let us get a 2nd FP for MS in that time frame, we were able to get a FP for Maelstrom). Went back to Epcot on 8/9, again around 5pm, got FP for MS again. Went back on 8/10 at 9am, went straight to MS, got a FP (it still showed that we could get another FP in 5 minutes, so we went to Test Track and got a FP)....along with the TT FP came a Surprise FP for MS that had to be used before 10am. We went back to MS and a CM asked if we saw that MS was on the park map....we still had our map from a couple of days earlier, so we said no, we just saw that it showed the future site and she said "No, as of today we are on the map, you need to get a new map". Later we did pick up a new map and a picture of MS has replaced the picture of TT on the front of the map and instead of "future site of MS", MS was now on the park map (and is listed as a FastPass attraction). Later, back at the resort, in the rack with the park maps, there was a separate card announcing Mission Space.
There is also a single rider line that is actively in use, but there wasn't always a line of people available (one of the times we rode, we had only three riders in our capsule).