Recall that high HDL is right now considered a good thing. Harvard says:

HDL is considered good because it takes the bad LDL out of your blood and keeps it from building up in the arteries. The standard recommendation has been to keep HDL levels high and LDL low.

But this new study is drawing that into question:

Here are current recommendations. Note that while LDL should be kept below 100, an HDL of 60 or above is still considered “heart protective.” That may change.