I bought a council "dalek" years ago from Surrey then topped up with one from Cambridgeshire many years later. In my last garden, which was small, I had three slots and two compost bins.
I'd rotate by taking the dalek off and putting it in the space then moving the contents back into it. Then I'd do the same with the other one into the space I'd just made. Any compost that was ready either went on the garden or into bags and stored behind the shed.
I found that it quite quickly rotted down and made room for more waste, I sited them on soil and they were in a south facing position.
I have the same system in my bigger garden but I sent off for another 4 daleks so I now have them in two sets of three with two spaces. I keep bags of "brown" to one side such as pampas grass clippings and stuff that's been through the chopper. I have a lot of grass clippings so I'm always sure to mix on the way in and I throw in some soil now and again too.
I'm happy with the system, it works for me.