See I was going to do this too and found there was no rss (only email prompt came up when I clicked on subscribe). Oh well I guess I'll just have to consume it as it appears on hn :(
Yeah, this works great for public/free Substacks. Unfortunately Substack doesn't offer any way to get a private RSS feed for subscribers, except for podcasts. So you end up with the truncated public versions of articles in the public RSS feed and have to click through and sign in to read the full one.