Hi Star and welcome!
When we've talked about exercise here in Maintainers, it seems like just about everyone has the same experience as Jessica/paperclippy.
Most of us do at least as much exercise as when we were in the weight loss phase. Some have really stepped it up and are running races, doing triathlons, or doing challenging gym workouts. All of which are much easier and more fun in smaller bodies!
The studies I've read all seem to say that exercise is even more critical to weight loss maintenance than to losing. In other words, it's possible to lose weight without exercise but it's really tough to keep it off without regular, sustained exercise. That's why some exercise recommendations are for more exercise in maintenance than while losing, such as the
Dietary Guidelines for Americans 2005, which recommends 60 - 90 minutes of exercise on most days to sustain a weight loss.
The National Weight Loss Registry is a study group of people who have lost at least 30 pounds and kept it off for at least a year (quite a few of us here in Maintainers are members!) Members of the NWLR do an average of an hour of exercise a day for maintenance. It's a group with about 4000 - 5000 members so it may give you a sense of what maintainers in a larger group than just 3FC do for exercise.
Personally, my exercise duration is about the same as when I was losing but it's more intense now. I only did steady state cardio during the year I was losing and now I incorporate HIIT into my cardio workouts. I've always tried to lift as heavy as possible, but now I really try to keep my heartrate elevated when I lift by taking minimal rests and supersetting.
It's fantastic that you enjoy running so much and it will be a huge help for you when you reach maintenance! I'd count on doing at least the same amount of exercise in maintenance as in weight loss, though you may change types, intensity, and other variables. What will change is being able to eat a few more calories.