Yes, what you need is the minimum amount of £62,500 to be in the account, untouched for the full 6 months.
So, you can withdraw and deposit anything above that amount, but you have to leave that base of £62,500 completely untouched.
So, for example, say you deposited £80,000 on April 15th. £62,500 of that must not be touched for the next 6 months... but you can do what you want with the other £17,500, so you can withdraw some of it and put some of it back in, and you can add to it, but you mustn't dip into the £62,500 at all.