Mates got ~$35K of shares sponsored into chess with RBS (formely ABN Amro Morgan)

He would like to sell and make better use of the cash through trading a medium/long term trend following strategy (story for another thread).

Can he sell these shares via any other means than through his sponsored broker? He does have an IB account, but hasn't transferred these shares over.

He can either suck up and accept the BS brokerage he'll be charged by his old BS brokerage firm, or transfer to IB which I believe can take a while? Can anyone confirm/deny?

Or any other suggestions?