I would see this as validation and simply carry on while learning from their mistakes. Also the day you launch you'd be exposing yourself and the idea greatly, so a month before or after means nothing.
Ask HN: Someone released my startup before me - now what?
11–13 of 13 posts
Re: Ask HN: Someone released my startup before me - now what?
#12I don't think it's too be an issue. You now have a chance to look at what solutions the competition has thought of and now you can incorporate and improve on some of their better features.
Also if your products are very similar, as you say, it will probably fall mainly on your marketing to who is more successful in the long run.
Re: Ask HN: Someone released my startup before me - now what?
#13There was a great conversation at: http://news.ycombinator.org/item?id=2931368 with regards to a similar issue with another member here on a throw away acount.