Last I heard, they were restoring everything they could before the list data was lost to the 'already read list'
Maybe after the lists data was lost, maybe some stuff you added to your 'currently reading' was previously in your 'want to read' and they say the receipts saying it was added to 'want to read' first. OR the devs are just adding stuff to 'want to read' to add it all into just one list.
I lowkey suggest not moving them around right now as we don't know where the site recovery is and some people today posted messages about having issues adding stuff to lists.
FAQ in case
https://www.mangago.me/home/mangatopic/21255174/

I'm sure most of us, or everyone, is still missing 'want to read' or 'currently reading' categories? Anyone heard from admins?