Confusion over Hillenburg's time at the Orange County Marine Institute

During my research for this one, I got a tad baffled on something: When exactly did Stephen Hillenburg work at the Orange County Marine Institute? I understand that Wikipedia's Good Article-class page on Hillenburg states from 1984 to 1987. The problem is, Hillenburg's The Intertidal Zone was published in 1989 yet he claimed he created it for the Marine Institute. So I did more digging and determined that most sources (including the Big Pop Fun interview and Who's Who in Animated Cartoons) never explicitly stated when Hillenburg was employed at the Marine Institute, just that he worked there for three years. I also found some reliable pre-2024 sources like a 2018 Washington Post article, which contains quotes from Hillenburg that state he worked on the comic in 1989.

Aside from the comic's 1989 copyright status, the official documentary "The Origin of SpongeBob SquarePants" explicitly states The Intertidal Zone was made that year. Perhaps Wikipedia did find a reliable source that insisted Hillenburg was employed from 1984 to 1987, but I'd conclude that said source is incorrect. Interestingly, Hillenburg mentioned in his Big Pop Fun interview that he landed two other jobs post-Humboldt before he got his then-dream job. My belief is that Hillenburg did not work at the Marine Institute immediately following Humboldt and instead likely worked there from 1986 to 1989. I think that makes more sense; had he left in 1987, it would have created an unexplained two-year gap before he studied Experimental Animation. Note that in his interview with the Princess Grace Foundation-USA, Hillenburg stated he began his studies in 1989, meaning The Intertidal Zone was likely completed just months before he left the Marine Institute.

I understand this is probably a pedantic point to raise. I just thought it was worth mentioning as there's been some confusion regarding when The Intertidal Zone was actually made. Heck, Encyclopedia SpongeBobia claims it was written in 1984! Ultimately, it's an example of what Wikipedia likes to call a "blind men and an elephant" situation. In some circumstances, typically reliable sources are not as dependable as one would expect!