Hard and soft links on client FS


I’m curious about how UB (client?) calculates the volume of data to be copied (e.g. under progress bar in “Activities” window)?
The question arises because I’m observing higher numbers in UB webUI than by client locally using ‘du’.
Does UB interprets multiple hard and soft links (on Linux client’s system) as same file?
If no, I suspect that file which has multiple hard/soft links is downloaded during full backup multiple times, isn’t?