Tbh, there isn't a lot to say about this episode. For those who were curious about Haruto's past, this pretty much reveals everything (well, since it is non-ero, it doesn't touch upon my suspicion that there was some classic Grisaia oneshota in there somewhere). It is pretty bloody - again, as usual - and it properly spotlights Haruto and the group of adults who raised him (questionable whether you can really call them adults, though).
That said, it should be noted that this is obviously setting things up for the plot of the series to take a big leap forward in the next entry. As such, we can hope that the next one will be longer and the final episode of the Phantom Trigger series, so Front Wing can produce something unique (in other words, a new series, hopefully), instead of throwing us tidbits of action once or twice a year.