It's a bit of a mess of people but also the same people.
It's something along the lines of..Matt Drake used to be rhythm guitar and vox, his brother Ol was guitars. Ol quit in 2013 and they replaced him with a guy who they didn't record with and lasted until 2018, then in 2018 Ol came back to do lead guitars. The band still didn't record and then Matt quit last year and they brought in a guy named Adam Smith, but he didn't sing so now Ol's doing the lead and the vox.
They also changed bassist in 2009 when their previous bassist died on tour. Technically while he isn't the only original member, drummer Ben Carter, is the only one who's been there from the inception of the band.