Note that some agents will advertise other projects as bukit puchong but they're actually a different location, through long winding roads

Location wise it's just next to Taylor's international school

The gallery is near Lotus's Bukit Puchong.
Official developer website:
https://www.ayer.com.my/dahliabukitpuchong
Call the number there to speak to developer staff.

I think they launch these in small pieces of land, so each time only a handful of units.

I am waiting for the next one

That's the curvy part of LDP as you traverse from Bukit Puchong/Puchong Perdana to Puteri, or from Putra Heights to Puchong Perdana

Lion, if you're interested, better go to the gallery soon, last I went there, the staff said not many units left

Look at the illustration photo at the bottom of the project page:
https://www.ayer.com.my/dahliabukitpuchong
2 blocks next to the international school, and not the land next to the access road (on its right in the photo). Means should have another phase / project soon, or is it for shops?

Dahlia is all sold out, freehold property really makes a difference