The dotted lines are created by the support of each parabolic bull run, which also makes the tops of the next bull market. The reversal happens when the resistance line is broken (red), which seems to happen at the dotted support line (green arrow). If this pattern holds true, the next break will be around April 2020 (tentatively). As always, could happen sooner or later, but this pattern has held true for each of BTCs previous bull runs.