Depends on how well you know the person. There was a girl I took some classes with a few years back, didn't see her after that, then ran into her after a few months on T and she seemed to recognise me, but didn't connect the dots - asked if I had a sister instead. Then there was a guy who owned an art shop in town, who I'd had a few long conversations with last year, partially transitioned, pre-T, and I saw him again last month and he didn't recognise me at all.
Voice is a different matter. Even my grandmother doesn't recognise my voice now. 😀