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tokens: to study time variations in the outer heliosphere and its interaction with the VLISM over more than half a solar cycle. They found that the globally distributed flux (GDF) and Ribbon evolved differently, with the GDF, which mostly arises from charge exchange in the heliosheath, exhibiting a leveling off and partial recovery of ENAs consistent with the prior output flattening and recovery of the solar wind output. In contrast, the ribbon showed a greater time delay and loss indicating a source of the Ribbon beyond the heliopause, most likely as a secondary ENA source—one of the six original ideas suggested by the IBEX team at the time of the discovery (McComas et al. 2009c ). Since then, a variety of more detailed physical processes for various types of secondary sources have been proposed (Chalov et al. 2010 ; Heerikhuisen et al. 2010 ; Schwadron McComas 2013 ; Isenberg 2014 ; Giacalone Jokipii 2015 ; Zirnstein et al. 2018a ). As also pointed out by McComas et al. ( 2017 ), in the second half of 2014 the dynamic pressure increased by ∼50% from ∼1.6 to ∼2.4 nPa and remained that way for at least the following couple of years. These authors discussed how such a persistent increase in the solar wind output and dynamic pressure should have a continuing major impact on evolution of the structure of the outer heliosphere and the returned ENAs. Specifically, they predicted that the ENA response should be (1) seen first from the direction of maximum heliosheath pressure ∼20° south of the upwind direction (McComas Schwadron 2014 ), (2) observed first in the highest energy ENAs, which travel back fastest and then extending to lower energies over time, and (3) followed a couple years later by changes from the Ribbon and back along the flanks of the heliosphere. IBEX observations generally bore out these predictions and McComas et al. ( 2018b ) showed that this large increase in solar wind dynamic pressure observed in the second half of 2014 at 1 au had begun to modify the heliosheath and produce enhanced higher energy ENA emissions observed near Earth by IBEX starting in late 2016. As predicted, the enhanced emissions were centered south of the upwind direction and were seen first in the higher energy ENAs. McComas et al. ( 2018b ) also combined the observations with MHD simulations to show that the heliosphere was re-expanding from this persistent pressure enhancement after at least a decade of diminished size. McComas et al. ( 2018b ) further connected the IBEX observations with simulations to show that this pressure enhancement also very likely produced the largest enhancement in heliosheath dynamic pressure seen at Voyager 2, which was observed in late 2015 (Richardson et al. 2017 ). The roughly one year between the Voyager 2 observation and pressure enhancement beginning at 1 au in late 2014 indicated that Voyager 2 observed a transient pressure wave in the heliosheath, which was launched by the supersonic solar wind reaching the termination