Back in 2017 a clear pattern emerged between Bitcoin and the altcoins. BTC was (and still is) the bellwether for the entire market, leading the peaks and troughs. However, they were also inversely correlated in that altcoins would often dump before Bitcoin made a big move.
The same could be happening again as Bitcoin maintains its hold on the $5,200 price level but its brethren start to fall back. As a result Bitcoin market dominance has climbed a percent or so back to 51.3% over the past week or two.