Marky, while fasting will contribute to lowering the BP, proper diet is needed to keep it down afterward.
I'd keep track of the BP by using my own BP monitor and measuring morning and/or evening after 30 min in seated position (no talking, no major muscle tension). As you progress with your fast your BP will make stop the meds. Diuretics would be bad while fasting, I can't tell you when to stop them unfortunately - ideally no later than the 2nd day on only Water Fast.
Let us know how you are progressing.