Her turbulent marriage ended earlier this year, but claims had surfaced in the press of secret trysts between them.
Blake appeared to be forgotten, though, as the bee-hived diva, looking relatively healthy and happy, spent the evening with singer Tyler James, once her labelmate at Island Records.
The pair, who dated back in 2003, seemed to have rekindled their relationship leaving a London restaurant hand-in-hand after a quiet dinner.
When a fan requested a kiss she explained politely: "Sorry, I'm with my boyfriend".
Tyler then accompanied her to the Jazz After Dark venue where she performed a note-perfect gig.
In contrast to Amy's chaotic appearance at the Saint Lucia jazz festival when she slurred her words and fell on stage, this was the second concert this week to go off without a hitch.
On Tuesday, the jazz chanteuse appeared at a charity fundraiser for terminally ill children, just round the corner from her Barnet home.
She surprised guests at the Rays Of Sunshine event with an impeccable five-song set.