Knowing you work full time. If this event is all you care about. Beyond your commute I wouldn't ride under 70% threshold.
Don't worry about a massive CTL. 100 will be enough.
Just concentrate on quality. 2x20. 3x20. 1x60 1x90 then more 3-4x10-15 as you get closer to event. Also work on your descending, you'll make loads of time up there. You can also do 1x90 and then go for a run at the weekend. Don't bother doing longer rides. Though if you want to go out riding do 2-3h rides at like 50+TSS per hour, keep it steady, just pushing along at a pace, not smashing hills. Or just ride you bike if you need to relax and not stress about training. If you actually enjoy riding a bike to just ride sometimes. Just do brick Workouts with increased total time when you have the time. So your body is used to it. But feel free to take a rest between. As you'll descent for 20 min. So you can do a little rest, or 2 harder more intense workouts split over the day. Learn to pace. So ramp your workout up as you go though. Don't start them too hard. If you're doing 1x60 at 300 watts goal, start at 270 and end at 330 if you have the legs. Better to complete the planned duration that pack in as you started too hard.
Quality.
Don't worry about pushing up CTL to a set number. Just plan your workouts in TP so that CTL is goin up. You properly don't want to be super fresh coming into this event, as its longer duration. However that's a personal body thing on what your TSb should be. Though maybe in the region of +10 is good.
Knowing you work full time. If this event is all you care about. Beyond your commute I wouldn't ride under 70% threshold.
Don't worry about a massive CTL. 100 will be enough.
Just concentrate on quality. 2x20. 3x20. 1x60 1x90 then more 3-4x10-15 as you get closer to event. Also work on your descending, you'll make loads of time up there. You can also do 1x90 and then go for a run at the weekend. Don't bother doing longer rides. Though if you want to go out riding do 2-3h rides at like 50+TSS per hour, keep it steady, just pushing along at a pace, not smashing hills. Or just ride you bike if you need to relax and not stress about training. If you actually enjoy riding a bike to just ride sometimes. Just do brick Workouts with increased total time when you have the time. So your body is used to it. But feel free to take a rest between. As you'll descent for 20 min. So you can do a little rest, or 2 harder more intense workouts split over the day. Learn to pace. So ramp your workout up as you go though. Don't start them too hard. If you're doing 1x60 at 300 watts goal, start at 270 and end at 330 if you have the legs. Better to complete the planned duration that pack in as you started too hard.
Quality.
Don't worry about pushing up CTL to a set number. Just plan your workouts in TP so that CTL is goin up. You properly don't want to be super fresh coming into this event, as its longer duration. However that's a personal body thing on what your TSb should be. Though maybe in the region of +10 is good.