bmi diamond club - Signup bonus miles

I have had some signup bonus miles in my account for the last few years and wanted to transfer them to BA Avios.
Has anyone had any problems transfering these type of points over to BA

Many thanks

BA

They are transferable to Avios, but not to other DC accounts through the family membership.

They are transferable to Avios, but not to other DC accounts through the family membership.

Thats what I had thought , but after a I tried a few times to transfer and failed even though the DC miles can be seen on BA I contacted DC, checked all details were in order. I emailed d......dot ETC and the reply was that signup bonus miles are not transferable to BA.
I have sent a PM to Nicci asking for clarification as she seems to have one foot in each camp at the moment.

B A Brown