Orange Livebox: Reported Speeds when Interleaved?

Hi,

I was looking at the connections stats on an Orange Livebox today and the
connection speeds were 8096 / 448.

However the line was set to Interleaved rather than Fast.

I was under then impression that the maximum line rate for Interleaved was
7616.

Does the Livebox display something other than Line Speed for it's connection
stats or is it just misreporting the speeds?

Kind Regards

Simon