PrimaryAssetLabel Chunk ID increased package time based on highest value used

I was doing some tests, and I wanted to come up with a formula for Chunk ID so that it is easier to separate the IDs based on the data is inside them (keeping in mind that the id is most likely an integer type), but I found that the ID is not used as a simple number because the higher the number I used, the longer it took to package the game.

For example for the highest number used:
300.000
AutomationTool executed for 0h 1m 47s
400.000
AutomationTool executed for 0h 2m 49s

What does it do behind the scene, that causes higher package time if larger id value is used?

As a note, the final game size was the same, as it doesn’t create more files then the number of PrimaryAssetLabel files + 1 for chunk 0.

It is true, you are not going to have that many chunk, I was using higher numbers just for organization purpose.