I got the Sleeper Simulant when it was available and I picked up the quest and did the first step for No Time To Explain yesterday, so I assume I'll be able to finish it, but I couldn't agree more. It blows that anyone who was on vacation or had plans either of those two days has missed the opportunity to get these guns until Bungie-only-knows when. I actually really like that stuff is becoming available over time. It's nice to have new stuff popping up now and then. But once a quest is in, it should stay in.