On my second rewatch of this series, I figured it'd be a nice time to watch this OVA as it's kind of a sequel to Ace of Diamond? MAL doesn't say so, but I say so, so here I am reviewing it.
So, the first episode is material we don't get from Ace of Diamond or Act II, so I enjoyed it a lot. The off-season is something I didn't really think we'd ever get to see in the main series, so I'm glad that this episode showed us what it's like and how it shaped the characters going forward. In that vein, you get to see Miyuki post-injury which actually allows for some character development on his end. In a way, we get to see a Miyuki that we haven't gotten to see before, which was really nice. The first episode, I felt, was true a epilogue to the series, and it did its job well.
The second episode was alright, but not exactly the same. It spends half the time following Jun and, subsequently, the third-years post-Inashiro loss up to right before the Spring Invitational. It does provide some character development for Jun and insight into the third-year's thought process when watching Seido make it to the Invitational, so if that's something that's interesting to you, you'll probably like this episode. I, personally, didn't find a lot of extra information through listening to Jun's story that I felt was necessary for enrichment of the plot, but it was still interesting. The last chunk of the episode was stuff we got from the end of Ace of Diamond and the beginning of Act II, so there isn't much to comment on.
As far as these two episodes go, it was really fun to see parts of the plot that aren't available to us otherwise, and it does serve to lead us into Act II; all in all, it's a good set of episodes to watch. I'm off to rewatch Act II in all its glory while waiting for more to come out, so I'll see you there one day!