Harmonix have addressed concerns of European fans on their blog where they have acknowledged issues with DLC on the European PS Store as well as low supplies of the game at European retailers.
Community manager Eric Pope says they've been working SCEE (Sony in Europe) to solve the issues and that a patch that will sort the majority of problems (currently 431 affected songs) on the PS Store is due in early December.
Additionally Pope commented on availability issues in Europe noting that fans can download a digital copy of the game, but that both the guitar version and Band in a Box version of the game have been in low supply worldwide.
"While we'll continue to have limited stock through the year's end, we'll see more flowing into retailers in 2016 to respond to the demand we've seen."
Pope also noted a selection of retailers where the game is in stock that included Argos, Amazon and GAME in the UK.