If you are still detoxing and feel fine with no hunger there is no need to stop at 40 days ryjola. If you still have the desire and motivation to stick with the fast until your detox is done and you feel natural hunger again then that would certainly be your best option. If you go to juice fasting then you will continue with the weight loss but it will be a lot slower, and you risk getting cravings for solid food when you start the juice as well. So it really depends how you feel.
36 days is awesome, well done! And good luck continuing towards your goal. :)