Walker takes up the newly expanded role with immediate effect, giving her responsibility for the line's wider UK commercial performance across sales, trade partnerships, distribution and market development.
She will retain leadership of the line's nine-strong UK trade sales team and take "strategic oversight" of a further three colleagues across trade engagement and international marketing.
The promotion follows an unusually busy summer for Walker and her team, with more than 1,200 First Mates experiencing Valiant Lady during the line's biggest-ever UK and Ireland trade activation.
The ship tour showcased Valiant Lady following its revamp, including the launch of Indian-inspired restaurant Ariya. Walker told TTG that around 950 of the 1,200 agents who attended had never experienced Virgin Voyages before.
The line also saw its biggest-ever revenue day on 13 August, surpassing its previous record set on Black Friday 2025. The record followed the launch of Virgin Voyages' inaugural Scandinavia and Baltics programme for 2028.
Walker said: "The momentum behind Virgin Voyages in the UK right now is incredible and I'm hugely excited to have the opportunity to lead the market through its next phase of growth.
"We've had a record-breaking summer, but what is most exciting is what sits behind those numbers. More First Mates are experiencing the brand, their confidence in selling us is growing and we're seeing customers come back to Virgin Voyages time and again."
Stephen Hopkins, Vice President of Growth and International Sales and Marketing, said the UK had become a "powerhouse market" for the cruise line.
"SJ has been instrumental in that journey," he said. "She combines a deep understanding of the UK trade with commercial ambition, infectious energy and a genuine passion for our brand and our partners."
He added that the expanded role recognised "the way she already thinks about the business as a whole".
The promotion comes as Virgin Voyages prepares for another push into the UK trade, following what Walker described in her recent TTG interview as a renewed focus on reaching agents through onboard, online and face-to-face activity.
While the line will not return Valiant Lady to Portsmouth next year, she also hinted that overseas ship visits for agents could form part of its 2027 trade strategy.