Welcome to the forum and good luck for the future !
I assume this is your second year on the NDA course after spending the first learning all the theory ?
I am an ex NCA [with Credit] student so know what it's like trying to find work in the UK where many farmers are struggling to survive let alone take on extra staff.
If I recall I and many of my classmates could only find work either night-lambing [great fun on a Welsh hillside with snow all around and a torch that struggled to show as much as a candles worth of light !] or else during silage/harvest time.
I would suggest reading the "Farmers Guardian" or "Farmers Weekly" which are usually full of jobs around this time.
I wish you well, keep in touch and let us know how you go eh ?!