A sub launched and surface launched variant is under development and being tested, but it is not yet in production. It looks like it will be a fine weapon.
My point was that the UK uses the Tomahawk now. You responded in your first post to tell me that the Royal Navy was not using US Tomohawks, but was using their own missile. I responded back by saying that ws not the case and linking to the Royal NAvy's own site where they list the Tomahawk as the missile being used by both the Trafalgar and Astute class submarines. Right now, there are no Storm Shadow SLCMs available for use by the RN. They are not being produced yet.
At some point in the future the RN may use the Storm Shadow in place of the Tomahawk, or use them oth. But right now, and certainly for any current or planned operation, the only sub launched cruise missile the RN uses is the Tomahawk.
No, I said Britain doesn’t rely on the Tomahawk. Not just the RN. I said Britain. Or more to the point, ‘we’. By which I meant the UK.