Do the the fuel efficiency upgrades actually work?

[Icewolf]

I've traded my A class system freighter for an S class vanitor freighter a week ago. I've installed all available s class fleet coordination upgrades six times, but i can see no difference in fuel consumption of my frigates. Same goes for the fleet speed upgrades. The other four upgrade types work.
Has it not been implemented yet? Or is it just me?

[ΔΙΑΚΟΣΙΑ]

Not just you.
The speed and fuel upgrades for the freighter don't work.
I tested this.

[Icewolf]

Ok, thanks.

[Mr. Bufferlow]

Have not messed with freighter stuff, the fuel efficiency upgrades for the ships work...but only apply to ship usage. Is it possible they work, just only for warp fuel usage?

[ΔΙΑΚΟΣΙΑ]

The hyperspace drive upgrades do affect your freighter's warp drive.

The test that I did:
1)Assign ships to an expedition. Make note of the fuel and time to completion.
2)Moved all six speed and fuel upgrades into one inventory.
3)Assign the SAME ships to the SAME expedition.
4)The result was that the fuel and time to completion were the same.
I tried this also with only moving one into the same inventory as 3 (leaving two active).

The S class speed modules go up to +15% expedition speed (total of 90% for 6).
The S class fuel modules go up to +20% expedition efficiency (total of 120% for 6).

It is possible to take the time to completion negative (instant expeditions) and have no fuel usage.