Garlic rust advice

I’m needing some advice on garlic rust. I have a bed with round 20 plants and it is badly infected by rust. I didn’t do anything with it, I just let the plants grow on.
I’m now not really sure what to do with them…I can’t tell if they are ready for harvest from the leaf colour due to the rust. I did take one bulb up and it was reasonable in size but the cloves were not separated.
Am I better to leave them to grow on or cut my losses and take them up to make space for the next crop?

I stopped growing garlic simply because of the fact that rust destroys the crop every year. Farmers must have some sort of product that prevents rust that is not available to gardeners. I am going to try growing some autumn planted garlic in my poly tunnel this year to see if I can get a crop as rust is a bit like blight it comes with the rain and it does not rain in a tunnel 
I will have to prepare the soil with plenty of compost and manure though as garlic needs very good soil to get decent bulbs.

Rust and Rot on mine again this year, got about half of the crop in a useable state. Will try one more time next year in my raised bed that has been used for carrots and will add a bit more protection which they will both appreciate.
Shame as its something to plant when not much else to do and low maintenance.