GP probably means stop -> market orders. When the stop price is reached, the order converts to market. Various brokers and exchanges offer more types of stop o

GP probably means stop -> market orders. When the stop price is reached, the order converts to market. Various brokers and exchanges offer more types of stop orders, such as stop -> limit, where you set a limit price, and your order becomes a limit order after the stop price is reached. Of course crypto exchanges take forever to implement new order types, and I'm not sure any of them have stop -> limit. Also, stop orders don't work in general in a slipping market because liquidity vanishes from the book.