In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.

Passage: In 1987 SST Records had purchased the Descendents' previous label New Alliance Records, releasing their 1987 album All and re-releasing all of their previous material. Following the Descendents' final tours in spring and summer 1987, singer Milo Aukerman had left the band to pursue a career in biochemistry. The remaining membersbassist Karl Alvarez, guitarist Stephen Egerton, and drummer Bill Stevensonrelaunched the band under the name All, releasing three albums on the SST subsidiary Cruz Records between 1988 and 1991 with singers Dave Smalley and Scott Reynolds. SST also released the Descendents live albums Liveage! (1987) and (1989), both recorded during the final two Descendents tours. Somery was released in 1991, compiling tracks from the Descendents' past studio releases. Stevenson created the cover art for the compilation while Egerton did the graphics. The Descendents would later reunite with Aukerman in 1995 to record Everything Sucks.
Link Information: Aukerman's first recording with Descendents was the Fat EP, released in 1981. Answer: 6
How long had Milo Aukerman been with the Descendent's before quitting?