I'm afraid I have no answers but I do have sympathy as I'm in exactly the same boat. I had ITB back end of last year on my left side. Manifested as pain in side of knee while running and severly after. I had two treatments of acupuncture and it was fixed!! Totally pain free running.
I then got it on the right knee and had 3 acupuncture sessions but although improved it didn't disappear. So I went to see a sports injury therapist who has given me strength exercises and stretching and told me to foam roll ALL THE TIME! She is massaging my glutes, quads and knee and says they're all tight. But four weeks into treatment there is very little progress. I can run for about 10-12 minutes and then pain starts.
I've read a lot on here and elsewhere about recovery time. It seems you can be looking long haul but I also know people who've sorted it for good in 6 weeks.
My problem is that I'm not seeing any progress despite rehab programme. And coupled with the fact that I got it fixed on left side without any foam rolling/exercises just makes me doubt the whole received wisdom about treating ITB.
I'm dealing with same time frames as you btw...my last pain free run was Jan.
So not sure what you can take away from this other than maybe try acupuncture? But if you do find anything that works please SHARE!!
Just entered (this morning) my first HM. My question follows on from the one above really about training. I want to do it in 1.40 and I currently run speed/interval sessions on track once a week with my running club, usually one long run a week (up to 8 miles currently but plan to increase one mile a week) and then another mid pace run inbetween (anything from 5k to 10k depending on how I feel!). Is this enough of a mix? I also take two spin classes and two strength/conditioning classes and a swim each week. The run is in October. My long run pace is about 8 min/miles and my 5k PB is 21.00 if that helps.