I've been shooting a lot of FP-4+ developed in Rodinal, shot in my Hasselblad. I expose at EI-100 and develop for 14 minutes at 68 degrees. Ilford's recommended time is 15 minutes but 14 worked better for me. I did some exposed at 50 and developed 10 minutes, to reduce contrast, and that worked well too. I'd probably go 11 minutes for your EI-64 shots. Contrast will be a little low if you shot with low contrast lighting (eg. overcast day) but will look great if it was a sunny day (contrasty light).
Shot at EI-100, developed 14 minutes in Rodinal 1+50, 68 deg (20 degrees Celcius).
Shot at EI-50 and developed in Rodinal 1+50 for 10 minutes. Both shots are Ilford FP-4+ 120 size.