(the) last (one) heard
According to the most recent knowledge one has about someone or something. Last we heard, she had moved up to Calgary to be closer to her family. I had no idea there were so many problems. The last I heard, everything was progressing smoothly.
the last I ˈheard
(spoken) used to give the most recent news you have about somebody/something: The last I heard he was still working at the garage.