First of all, June' is the largest company of its kind in North America, with several branches and web stores that have no problem selling hundreds of other titles.
Wow, that's news to me.
Since I started this thread, I'm going to comment here:
Not all publishers are perfect. Dark Horse manga has pretty much been late on 90% of everything it's ever brought over from Japan. Don't get me started on Seven Seas, and some others... While we're on the subject, what you said and I quoted above did make me smile because you can still be a small publisher and have many imprints; I think DMP is doing the best they can with the resources they have.
As for release dates - Book distributors demand a concrete date to give vendors like Amazon and Barnes/Noble; but producing more than one title is never an exact science. The variables can be pretty intense: if the pre-press, editing, and proofing process for any given title has the slightest of hiccups [such as one title delayed because another is lagging in proofing] then the publisher has to make the decision which book to print in its place, or how much time to delay it. You simply can't send 10 titles at once to the printers, because those people expect to be paid cash up front - so printing one to two titles at a time, spreading out their print dates, is crucial. Sending a bunch of titles to the printer in tandem is expensive and can be costly if anything goes wrong; best to miss a projected release date by one month, then to release a slew of misprinted or poorly printed books. DMP has made some strides in bettering the quality of their titles - if this means a few delays, then so be it. [my opinion]. They're not VIZ, or a manga publisher funded by a 'NY publishing house - they don't have an army of contracted editors and offices out the wazoo.
Technically, they're still a small company, so things like spaced out print-schedules are neccessary in order to release the books they do; without going cash poor.
In this case of Maiden Rose, I guess there's been a delay due to 'too many titles at the printer' right now [or too many titles in production]? I'm glad someone has come on this forum and told you so, something many BL pubs don't so. Again, sorry MR is delayed and you don't have it yet - I know this sucks.