What makes Upper Ninety by Russian Circles notable?

'Upper Ninety' helped solidify Russian Circles' place within the post-rock and metal communities, garnering attention for its intricate instrumental compositions. The EP was well-received in underground circles and contributed to their growing reputation, leading to opportunities to tour with other prominent bands in the genre. Released in January 2006, 'Upper Ninety' was Russian Circles' debut EP, marking the band's entrance into the post-metal scene. At this point, they were establishing their sound after forming just a year prior, setting the stage for their first full-length album later that same year.