Technically you should not be using emergency funds to buy dips.. but you can use reserve funds. Yeah of course people call these things different things, but the idea of emergency funds is to have money to live and to pay for your expense if an actual emergency takes place or if you lose your income for some reason, you have a little bit of breathing space.
Reserve funds would be extra money, so you should never dip into your emergency funds for anything other than needing to live because you ran out of other money.
I think this has been discussed some months back. Money that is kept for an emergency is not to invest in bitcoin and if anyone wants to invest in Bitcoin then extra funds Shou be made available if only the person is really ready to invest. There are some banking apps that one can use to lock funds by weekly, monthly and yearly. The person can choose the plan he wants and I normally select two plans to lock my funds in weekly and monthly because I don't know when the dip would come and if it comes, and fall under the weekly plan then I would use it to buy the dip and I will wait for the monthly plan again and once it unlocked I would use the money to buy the dip again. So with that you don't have to spend your emergency funds again.
Now if you buy the dip with the emergency money and something happens within the week and you don't have extra money to solve the emergency need, you have to make a sale of the bitcoin investment you initiated in the week to solve the emergency and if the dip is below the purchase price of bitcoin then you are at the losing side of the investment because you did plan well for the investment. Always keep the emergency funds down the emergency purpose and not to buy the dip.