Hi,
I got this mail from TomTom this morning:
Look forward to a new TomTom device
We have discovered that your current sat nav is not compatible with the latest TomTom map update and needs to be replaced. It's been a while since your Rider 550 was last updated. Roads change all the time, so we are constantly updating our maps.
But don't worry: we have the right hardware upgrade for you to get you to your destination even easier and faster. To make the change easier for you, we're offering an exclusive 35% discount.
If you follow the Link, you get the current Rider 550 without any discount.
I have already a Rider 550.
What is going on at TT?
I no longer understand this corporate policy.
Good that I changed to MRA. 
I hope it will stay longer. 