Why have The Simpsons IMDB ratings randomly TANKED

I was browsing the new Simpsons IMDB episodes and I noticed all of a sudden the ratings different from the last time I checked. I then went searching and found that all of a sudden Season 32 and Season 33 are about -0.3 stars less than what they were last week Monday. 

I only have limited proof but see below. Anybody who has been collecting Simpsons IMDB ratings would probably have more proof as well.

https://www.neetcoder.com/app/graph/tt0096697/The%20Simpsons

Using this website you can see all of the Simpsons episodes, you can see serious Flanders part 2 was a 8.6 but now it’s an 8.3. Another example is The Last Barfighter dropping from 7.7 to 7.4

I know imdb uses a weighted average but I don’t see how this can explain all of a sudden the past 2 seasons dropping consistently by 0.3 stars but not the others.