Good morning
@Polite …. I live about 65km south of St Malo and cycle quite extensively in central Brittany.
If you need any detailed help planning your route south from St Malo to say, Nantes, please ask me.
My neighbour lived in La Rochelle for years - so again if you have any general questions about that area, then fire away
There is quite a lot of literature out there on the EV1 cycleroute (Roscoff to Biarritz, if memory serves) so that should help you with route planning