When adding a fuel up on the mobile site (as I commonly do) the MPG has been reported incorrectly. When on the main site, my vehicle is tagged correctly in UK MPG, but it appears the mobile site is erroneously showing the MPG in US MPG.
And there I was thinking the Disco was doing exceedingly badly and wondering if something was wrong!
I have checked, and have Litres selected for reporting purposes BTW.
Try navigating directly to the mobile home page at m.fuelly.com on your phone and click the "Set Units" link. That will tell what units you have set for reporting at the mobile site. It's possible it got reset at some point to US reporting. If it says "US", click "UK" to reset things.
It would appear I wasn't using the mobile site actually, but the main site, and it was using US units in the top left of the screen. Yet the site on my PC has always been on UK units....
Also Time Offset in the Settings should be adjusted to "Time Zone" with the appropriate zone names & offsets listed - saves you from having to work out what the applicable offset is for your time zone...
It might be worth clicking on "Settings" on the left menu and making sure that "Display Units" is set to "UK". That should make your choice permanent for any device you use to log in.