“ Please note, this experience is fully booked up until October 2019 and is fully booked on Saturdays until November 2019 “ Most likely closed down due to virus by then (lol)
I bought this when it was heavily discounted last year, and the voucher period ended before there were any available booking slots. If you are able to go on a weekday that isn't a Friday, then it might be worth it. If you can only do weekends, then there is unlikely to be a slot for you.
Code can be used on other items too https://www.hotukdeals.com/deals/buy-a-gift-are-offering-10-off-a-20-spend-or-20-off-a-60-or-30-off-a-90-using-the-code-mum-example-in-description-at-buy-a-gift-3421597