this EXACT thing happened to me.I've had my new Homage for less than a month and just yesterday the rear Suntour shock was completely flat. I noticed as I went to take it out of the garage in the morning after last taking it out the night before.
The bike shop has said they'll look at the shock after I asked for a replacement, but it's a little discomforting knowing that it will go flat at any moment in time.
One surprising feature I didn't know about are the snap release type connections on the mudguards. I somehow ended up with a stick in the front wheel and it didn't break the mudguard! Which isn't true for the last bike I had! It was as simple as popping the connections back together.
The replacement shock has lasted about 18 months, but I'm upgrading as soon as I can afford it.