Hey James
I live in Newfoundland and regularly cycle from mid March until snow, mid January this year. Last season I did over 5000 miles. I don't ride in the rain or when the winds exceed 35kph. Cycling uses more musles than a stationary bike, think back, shoulders, and arms. I ride stationary in the off months and it helps keep the legs and wind at a decent level but when I get back to cycling it takes a few weeks to reaclimatize. There are a lot of hills here as you know and gusty winds, that's something that's hard to simulate on a stationary. I turned 54 this year and have done 2 centuries this season. My usual rides are between 30 and 50 miles.