I’m 5’9", 55yo, 201# (and dropping). FTP is 310ish, ride 8-11 hrs per week this year.
Looks like the average daily carb intake is 225-275g. Zone 2 days (typically 1.5 hrs each) and off days I’m often at 150-175g, and days with intensity are in the 300-400g+ range.
I wouldn’t target a specific goal for carbs. It should vary drastically depending on workouts. You can target certain macro goals for fat and protein and fill in the rest with carbs though. But either way, increasing is sure to help no matter how you go about it.