2010–11 season saw Lines recording a number of good results in the newly introduced minor-ranking PTC events, with three last 16 appearances and a quarter-final at the Event 5 to his name. However, his performances in the major tournaments were less successful, as aside from the UK Championship last 48 appearance he managed to win only one more match; as a result he couldn't improve his ranking at the end of the season. Lines qualified for the 2011 UK Championship by defeating Ken Doherty 6–5 in round 4 of qualifying. He played Martin Gould in the last 32 and was beaten 6–2. Lines qualified for the 2013 German Masters by defeating John Higgins 5–3 in round 4 of qualifying. He played Ken Doherty in the last 32 and won 5–3, before losing 3–5 to Marco Fu in the last 16. In June 2014 he won the Pink Ribbon pro–am event defeating Lee Walker 4–1 in the final. Lines the Yorkshireman beat defending champion Neil Robertson on a run to the last 32 of the 2016 UK Championship. In March 2017 he won the World Seniors Championship defeating John Parrott 4–0 in the final. Lines regained full professional status for the 2017–18 season by coming through an EBSA playoff. He defeated Zack Richardson 4–0 in the final round. He reached the last 16 on two occasions during the 2017/18 campaign, at the 2017 Paul Hunter Classic and the 2017 European Masters. Lines famously has a 4-3 (excluding the Shoot-Out) winning head-to-head record against 4-time World Champion John Higgins.