Currently on the main bmi Diamond Club page is an offer to join the program (promotion code FF19KD) and receive 9,000 miles straight away.
Terms and conditions of the offer are pretty much as you’d expect: you get 9,000 miles added to your account within 3 business days of signup, and don’t you dare open up a second account for the purpose of taking advantage of this offer!
I’d save up my miles rather than just grabbing the free redemption this offers, however:
9,000 destinations miles is sufficient for 1 return direct flight with bmi or our Star Alliance partners in the UK, or between the UK and Austria, Belgium, France, Germany, Luxembourg, Netherlands, Republic of Ireland, Switzerland. All flights are strictly subject to availability.
The real value in the bmi program is cash and points awards. See the award chart for details. Premium economy is just a 25% increase in mileage and cash if applicable, business just 50% more, and first can always be had for double the miles (and cash).
Be patient with the website, it’s been known to be slow or glitchy, but it’s a pretty good program and 9000 free miles is certainly worth it. By the way, they’re a Star Alliance carrier and are the only non-US based member which regularly offers status matches. So possibly time to take a look!
MileMaven for the pointer.)