Yes, as mentioned the BA/BMI website says you earn the miles and staus , but why then they say differently. As for the checkin desk there is no BMI staff at RUH and though it is possible to take the flIght and make a claim later , if BA says BMI and Diamond club no longer exists, then there is no point in using BMI or Diamond club for 50% less miles and no status, compared to BA silver/gold. At present with 32k BMI status and only needing 6k more to gold status , there must be many other BMI members either needing to renew or increase status level you can no longer do it according to BA.