St Martins Island (Dhaka)

Hello, I have friends coming in November and we are wanting to go to St Martins Island for a couple of days diving. Has anyone been there and could give some advice on a good dive company there? We all have open water dive certificates but are used to diving with a very well established dive company.

We are also hoping to go to the ship breakers yard but have heard conflicting information on access, has anyone been recently?

Any suggestions greatly appreciated
thanks in advance