Thanks for the replies guys. I have indeed seem a physio, who gave me a telling off because I had come back to sprinting without properly rehabilitation after coming out of cast in the spring. My calf wasn’t strong enough and my achilles took to much of the load.
I’ve been doing eccentrics in high volumes for about 8 weeks and dropped all running. My coach massages my calf and soleus every training session, along with mobilising my hips. I’m having acupuncture next week also. The pain seems to have subsided, and I am running using an achilles strap at the moment. However, jumping straight into GPP hills now will probably set it off again.