Online application and right after the numerical and logical online tests. I got scheduled for a call interview with basic kind of questions (Why UBS? Why IB? What makes an intern successful in IBD? Teamwork example, UBS Deals, Risks and Challenges of M&A, which companies would you merge?, where would you invest 1 MLN £?, what Motivates you?), after more than 3 weeks they told me I passed to the next stage and I went to the assessment center at the UBS office. There I had: SHL numerical test (harder and less time than the one online), individual presentation, technical interview, competency interview, group work).
Got rejected the day after with an email.