Thanks mlivshin, I have decided to not update my i40 since it works perfectly and has HSS on my X-T! which I intend to keep. I can still use the i40 as a slave on my X-T2 which is fine. I also discovered I can use the i40 in manual mode on camera if I place a Yonguo trigger under it.
For TTL on the X-T2 I bought a Fuji EF-42.
I really like having HSS on the X-T! and will not risk losing it.