I think it would be logical for the government to still be secretly operating in some capacity. This far along, you have to wonder what they'd actually be doing at this point. Recording history? looking for a cure/some kind of solution to the zombie infestation? Trying to save the American way of life? Just trying to survive like everyone else? I would expect that high ranking officials have some sort of plan in the event of a doomsday scenario and considering the region that Rick and them are currently residing, it seems inevitable that the show would eventually go down this path. I mean, how many bad guys can they continue to encounter/fight? It could also be associated with the woman who was dealing information. If they come from an extremely large community, its possible they have the resources to have an operating helicopter. perhaps the helicopter is how they scout. How else do you think they know about the other local communities?

 

Whatever group it is, this is going to have a huge impact on how closely the show follows the comic from here on out.

I'm not a comic reader and only know tid bits from things I've read here. So if I make a mistake, forgive my soul. Also there may be spoilers here....so continue with caution.

The only group in the comics, from this point out, that could/does have a helicopter would be the commonwealth. We know that story doesn't happen for a long time. Time jump, whisperers, among other stories that happen first.

Or it's a new group, not from the comics. Could be a military outpost, but that's sort of been done in ftwd. Could just be a group who happens to have a helicopter.

If I had to guess, I would say this is a slow introduction. S9 gets back to basics. Hilltop, Alexandria, Kingdom all rebuilding after the war. A season of character and world building. How they are dealing with the events of the war, how they are effected by the things they did and experienced. All while they rebuild their communities and relationships. Introduce the whisperers but in a much smaller, condensed story. Sort of how the wolves, terminus, and claimers were all bad groups but each story arc was fairly short. Less focus on "bad guys" and more focus on rebuilding.

As we get into s10, then we find out that Georgie is a scout for the commonwealth and was only willing to share info because she saw the events of the war and wasn't convinced Rick was a good person and the people weren't all good people. So the book she gave Maggie was a test. Give them the tools to rebuild a productive community and see what happens. If Maggie shares this knowledge with the other two communities and they use this tool and build a peaceful, functional society among the groups. Then she will introduce them to the commonwealth in s10.

Pure speculation on my part. But I think they are seeing the writing on the wall and understand things need to change and possibly hurry up and get closer to the end game. So change the pace of s9, get away from the idea of groups fighting, and get closer to the next big chapter. So if it has to end in s10, or 11, they have that clean ending ready to go.

 

I think your speculation is not too far from what is actually going to happen. The helicopter might belong to a well established and very large community (perhaps a few thousands) and the show will stop when Rick + others join this community for good.

 

Would make for an easy exit for the show.

S9 no time jump, rebuilding the communities, dealing with the aftermath, emotionally and physically.
S10 time jump, whisperers, tail end of season commonwealth introduced and they find out it's all been a test.
S11 Inside the commonwealth, working together, end of season/show the group enters and becomes part of it.

I still want to see a large time jump for the final shot. Adult Judith as the leader of the commonwealth. And as painful as this might be for some, an old man Daryl standing behind her, watching her as a protector and the last man standing.

 

Maybe as the commonwealth leader, adult Judith has a younger sister (offspring of Rick+Michonne) and an Asian looking right hand man (offspring of Glenn and Maggie) as well.
And maybe, the final scene shows her writing a book and this whole show is her recount of the whole history.