Actually, the Supreme Court simply affirmed the lower court’s ruling (gave lots of reasoning behind the affirmation, but the upshot is that the lower verdict rules). DC will have to deal with Judge Silverman, who months ago made it clear he’s tired with DC’s shenanigans. DC got their stay of Silverman’s ruling, SCOTUS affirmed the ruling, and now in defiance of Silverman’s crystal-clear verdict DC is re-enacting 85% of what they were doing in the first place.
Upshot: it doesn’t have to reach SCOTUS again. The circuit judges will take care of this.
It would be a wholesome thing for the DC Circuit to hold DC to "strict scrutiny", but I'm not sure that you are correct regarding the Circuit Court decision. I think the Supreme Court decision was narrower and avoided applying any particular level of scrutiny. I will re-read Heller to see if this is made clear or not.