Hi! I have the same spots on my Hoya callistophylla as user natydali was reporting. Wondering, what it can be. I ordered the Hoyas from Thailand to Germany in August and one week after I unwrapped them they all of a sudden started to show these halo like red spots.
Did you come up with some new information?
I will start a fungicide treatment, although I suppose that these spots were caused my the stress the plant experienced during the shipping.
