As one of the first steps of the integration process, British Airways is now matching British Midland members to equivalent elite tiers in the Executive Club program. Diamond Club Silver members get Executive Club Silver status, while Diamond Club Gold members get Executive Club Gold status.
To apply for a status match simply go to this page and input your Diamond Club account information.
Gary says that matched status is valid for 12 months from the time it’s requested. I’m quite excited about this, because British Airways Gold status gets you access to the OneWorld first class lounges whenever you’re flying, even domestically. That means as a BA Gold member I’d get access to American’s Flagship Lounges when flying domestically (I already get access to them when flying internationally thanks to my Executive Platinum status with American, though they don’t give you access on domestic flights).
It’s also worth noting that British Airways does soft landings, so if you don’t requalify for Gold you get Silver for the following year, and if you don’t requalify for Silver you get Bronze for the following year.
Lastly, while they’re now matching status, you can’t yet transfer miles from Diamond Club to Executive Club, or vice versa.