Light rebuild only for one object at a level with many objects

Hi, I’m a UE beginner and I downloaded and looked at Isac Crawford’s abandoned apartment demo.
At first, light build and shader compilation took a lot of time, but after completion, they were able to navigate through beautiful levels at 15 to 20 fps.

I added an asset that I made myself to the level for practice. Then a message was displayed at the top left of the viewport saying that a light rebuild is needed for one object.

I ran the Build Lighting Only command and it looked like the UE was rebuilding the light for the entire level. I expected the light to be rebuilt quickly because only 1asset was added, but it didn’t and it took a lot of time again.

Q: Does the light rebuild target the entire level originally? If not, is there an option to rebuild for only 1asset?

Hi, AFAIK you can only build lightning for the whole level (you can read through this here Lightmap build for selected objects only.), so if you place something new in the level and rebuild lightning, it will again build lightning for everything. You can set the Lightning Quality to Preview to make the building faster (ofc with less quality).