THE Staves's second album, If I Was, was pencilled in for release last September, then firmed up for February 2, only to be held back to March 23.

Why? The songs are ready, the album livery is complete, and the harmony-singing Staveley-Taylor sisters from Hertfordshire are on the road, showcasing the ripest fruits of their recording sessions with Bon Iver’s Justin Vernon at his April Base studios in Eau Claire, Wisconsin.

If Bon Iver's For Emma, Forever Ago charted the end of a love affair, then If I Was is a beautiful new musical relationship that deserves to take The Staves to bigger platforms. That's why it was such a delight to encounter the early days of this new blossoming at a sold-out Pocklington Arts Centre on Monday, three years on from the refined English Americana of 2012's debut album, Dead & Born & Grown.

If I Was is made of darker stuff, its arrangements more varied too, and so The Staves are touring as a six-piece, supplemented by three men in a back row of drums, bass and guitars and keys.

The sisters form the front line, each as individual in their dress code as they are in their vocal style. Camilla takes the centre, more intense than her siblings, with a crystal folk voice; Jessica, to her left, combines guitar with soulful pop chops; Emily, to her right, glides between keyboards, squeezebox, occasional percussion and hand claps, adding a cool country air when she sings.

Their set accommodates nine songs off If I Was, the best of them Blood I Bled, No Me No You No More and Teeth White, complemented by five from their debut and the hushed beauty of Open off last year's Blood I Bled EP. The sisters form an a cappella huddle for encore Wisely And Slow before breaking out, their flower in full bloom.

The second coming of The Staves can't come soon enough. Record company please take note.