The price of BTC above the 50 SMA is not necessarily an uptrend yet. It depends on the time frame you choose and needs to consider the nearest trendline to identify in the short / long term trend.
To talk about DCA, you should not consider too much about Technical Analysis as that is Holder's story. DCA belongs to the pricing strategy that you plan to buy when the price goes up or down. So the best strategy here is to depend on your FA analysis skills. A vision and a pre-set plan will determine the success of your DCA.