I am currently undertaking the modular route and am eagerly awaiting my phase 2 results (holding my breath in relation to Gen Nav and flight planning).
I have been and continue to receive a discount in relation to my council tax as I am considered to be a student. All you need do is get a certified letter from your training organisation (flying school) that verifies you to indeed be a student, give this to the council and they will provide you with the discount.
In fact this was never in doubt or questioned. Again, it would appear that certain indiviguals on Prune just want to comment on the negative, i.e. you were lucky blah blah blah
. Get the letter, go back to the council and try again.