So, I decided to look into heyward's starts tonight cuz i'm a nerd like that. I had a more lengthy post typed up but I know i tend to be wordy so I'll summarize. His triple slash is probably slightly unsustainable but stat casts has basically all his hitting metrics in the 82nd percentile or better which is really good. His walk rate is the best of his career which coincides with the highest hard hit rate of his career and the lowest k rate. My guess is all that is tied together. The thought there being pitchers are having to respect his power and he already had a good eye leading to more walks. That also likely leads to fewer k's because pitchers are more worried this year about being in the zone.
Simply stated, this is the best his bat has looked from the underlying metrics since his rookie year where he had a 134 wRC+. However that year he k'd 20.5% and this year thus far he's at 8.0%. Statcast basically expects him to have been a .320/.393/.510 hitter based on his results. For context, Goldscmidt last year hit .290/.389/.533 and was a 145 wRC+. When you add in he's a decent defender in a some what valuable position be it CF or RF if that sort of offense continues you're likely talking in the discussion for NL MVP.
Obviously there's a lot of season left and things could go wrong but given how things haven't worked out well for Heyward thus far I think it's worth celebrating just how good he's been thus far.