Susan came to the party yesterday, but it was already half past eight when she turned up.

苏珊昨天来参加聚会了，但她来的时候已经八点半了。

youdao

We were looking for her when she turned up.

我们正在找她，偏巧她来了。

《新英汉大辞典》

Walsh had been drinking when she turned up at Maire Rankin's door that Christmas Eve night in 2008.

BBC: 'Chilling act' - Rankin family on mother's killing

And so when she turned up your guys were surprised were they?

BBC: News Online

Earlier this year she was booed by fans at the London premiere of Crossroads when she turned up late and refused to pose for photos or sign any autographs.

BBC: Spears to take sabbatical