ATR72 range test - Is it way off somewhere?

Hey everyone! I was trying to reproduce the currently longest public turboprop flight, which apparently is Volgograd-Tyumen (URWW to USTR). According to World Map, this exceeds for a little bit the max range with full fuel of the ATR72.

I gave it a try, with both max fuel and max load. FL240 for cruising, cruise mode “long range”, the AP set 219K for crusing but never achieved it, 200 was max, but most of the flight was around 190KN IAS.

So, to my surprise upon landing I used less than half the fuel, apparently I still have more than half (2850kg remaining on board), this told by the FMC and MS Weight and Balance window:

Did have a slight tail wind, but really slight, impossible that it had this impact. So… someone knows what the heck is going on :D?

I don’t know if someone already posted something about this (searched but couldn’t find anything), but is really weird actually. My only explanation is that something is really badly coded because there’s no way I can two fold the range, much less with complete possible payload after full fuel.

Thanks ans best!
Seb