Thanks to Manfrotto, my legs collapse after snapping

I have used Manfrotto tripods for many many years with no problems whatsoever. So why is it that when I splash out on their most expensive 055 in the range, Carbon Fibre version, I have had TWO leg lever castings break on me (see pic) !!! Both times at the start of a shoot which has meant seriously hindered shooting and even worse, getting spares is now taking weeks!

The first snapped 6 weeks ago and Johnsons Photopia rapidly sourced another one, fortunately under guarantee. Now Johnsons have been 'let go' and a new amalgamated unit has taken over Manfrotto servicing and repairs, but they have none in stock and it will take two weeks to get one spare part!!!

So I have had to go back to my old 144 tripod once again with it's indestructible leg levers.

I use the tripods at the sea shore so they get rusty and salty but this has never resulted in anything worse before. This Carbon Fibre version seems doomed!