We know the new Subs if we can find the manpower to operate them...

We know the new Subs if we can find the manpower to operate them will be of limited use in tracking fishing type boats in a huge coast line such as we have.

Yes, recruiting and retaining defence personnel is a problem that needs a solution.
The latest review recommending the retirement of our sitting duck warships and investing in ships bristling with missiles along with many more smaller vessels to increase the fleet numbers. All those planned ships and not enough personnel to crew them.
We might be relying on foreign nationals.