Achilles Tendonitis

So my Achilles tendon has flared up again, which means I have to lay off running for a while :( I injured it a few years back, and from time to time it gives me trouble. Any suggestions for stretching/strengthening exercises that might help? I have been doing eccentric heel drops (as my physio showed me) and some calf stretches, and I have switched to low impact/strength training workouts instead of high impact HIIT type workouts, but I was wondering if anyone had any other suggestions?