What a teaser!!! We only get to see those pics of the bike?
I agree I am pretty sure they are for mudguards, that might be a
french thing to mount them away from the drops.
A pic from the rear may make whatever that tab looking thing is more obvious. Does it look like it is bent or broken? It seems in an odd spot for a chain rest.
__________________
“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk