Thankfully, I've been able to watch the first episode just before the second one starts airing.
I do have to admit that for the continuation season of the series this starter episode was rather eventful, giving hints for a few plot machinations in the future.
And, again my hunch was right when confirming that the ending theme played on episode thirteen comes from the second season.
It was a rather good episode.
Spoiler:
We got to see Kamika again in sword-and-slash action for a few seconds.
Sadahiro is quite fast on his feet and reflexes to have been able to surround Akasha and threatened the latter with a knife at point-blank range.
And, then the climax with Makina resurfacing from her depressive state, thanks to Ouri's hug
, and smashing the pulp out of the Shikabane-converted, monk's skull.
BTW, the jukebox rendition to the OP song is beautiful.