DCA method is an investment method through which you can buy Bitcoin at any time at any price. DCA method never helps you to hold your holdings long-term. Holding it long-term depends entirely on you.
Yes long term holding requires long term planning. There are many people who bought bitcoins using DCA tricks but could not hold them for a long time, it is seen that many panic and sell them. DCA strategy is the way to slowly accumulate bitcoins and DCA strategy is the way to buy bitcoins at an average price. So long term planning is required to hold long term investment, no one can succeed without planning. Before doing any work we need to plan, if you can't hold long term then investing in Bitcoin is not for you, because short term investment can lead to loss instead of profit.