Sell the turbo, council gym for £18/months and spinning classes, for the price of a cheep turbo you could get 5 months gym membership and pretty girls arses to stare at.
Either that or the old time triallist’s favourite, 2×20 is probably the most relavent to this time of year. Builds threshold power which is what you really want to be doing to make your mates suffer on the climbs.
10 min warmup, starting slow and building upto a couple of short hard efforts to get the blood pumping.
Set the resitance to a power(speed)* you can sustain for 20min
Easy spinning to recover.
Another 20min at exactly the same power(speed) as before.
Cool down.
The aim is to find a power that makes you puke at 19:59 on the second interval (not to die at the end of the first then go slow in the second).
Then repeat 48 hours later, but try it 0.1mph faster (but don’t touch the turbos resistance dial).
You could do shorter intervals, but there’s little point (appart from boredom relief). You lose the top end first, so doing sprints and anaerobic work now and that training will be of no benifit if you do more aerobic work later on. Whereas doing aerobic work now and that fitness stays long enough for you to taper through 20-10-5min-30s intervals over the months/weeks before whatever your target is for next season.
* power = force x velocity, so fix the resistance (the dial on the turbo, the tyre pressure and how much you squash it on the roller have to be identical every time you use it) and use a cheep £7 cycle computer from halfords to measure rear wheel speed. All you need is a timer, current speed and average speed and an easy way to re-set it between inetervals.