New answers tagged chronology
In this all-too-detailed layout, the events in GotG begin to happen on August 1, 2014. This is just a short time after the events of T:TDW and CA:TWS.
As you say, the film starts in 1988: Then, right after the Marvel logo: So, it takes place in 2014. Marvel has also published a prequel comic, that establishes that GotG takes place after The Collector receives the Aether.
Well, there's a trope for it, so apparently it happens often enough. I knew this had happened with Star Trek: TOS and Lost, but that link above has quite a few other examples.
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