I found this 'hidden' im amongst the refund conditions on my H&M receipt in the Melbourne, Australia Store (The first Australian store has just opened here). So after you make your first purchase (It appears this could be for any purchase value - my purchase was $70).
Then turn up ONLY between the 10-30 April with your receipt and if you get items to the value of 100 dollars or more, they'll take $20 dollars off!
****IMPORTANT**** You need your OWN full receipt- this image won't get you the offer! Its just to show where its located on your receipt. So if you turn up with this picture - it'll be an epic fail***
It says one customer per transaction, but you can go shop with a freind and buy together (if you both aren't buying that much).
They handed out a brochure which has their normal opening hours as:
Monday to wed - 9am to 7pm
Thurs / Fri - 9am to 9pm
Saturday - 9am to 8pm
Sunday - 10am to 7pm