Past perfect after before
We can also use before + past perfect to show that an action was not done or was incomplete when the past simple action happened.
He couldn't make a sandwich because he'd forgotten to buy bread.
The hotel was full, so I was glad that we'd booked in advance.
My new job wasn't exactly what I’d expected.
They left before I'd spoken to them.
Sadly, the author died before he'd finished the series.