I will just leave this recent study here:

https://www.duh.de/presse/pressemitteilungen/pressemitteilung/deutsche-umwelthilfe-belegt-hvo100-aus-altspeiseoel-klimaschaedlicher-als-fossiler-diesel-1/

Sorry for the German, here’s a translation of the abstract:

German Environmental Aid (DUH) proves: HVO100 from used cooking oil is more harmful to the climate than fossil diesel

• New study commissioned by DUH: HVO100 and “bio” diesel from used cooking oil are even more harmful to the climate than fossil diesel, taken as a whole from production to consumption.

• Promises of almost 90 percent CO2 savings refuted, as shifting effects boost climate-damaging palm oil production.

• DUH calls on the German government to stop the use and promotion of HVO100 from used cooking oil in road transport.