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tokens: field strength in their study does not hold below 10 G, which is a typical mean field strength for CHs. In our study, the rates of change in mean FIP bias in the small flux regions during their late-decay phase are significantly faster than the rates of change observed in larger decaying ARs. Baker et al. ( 2015 ) and Ko et al. ( 2016 ) find remarkably similar rates of decreasing mean FIP bias in the range [0.004, 0.009] h −1 within the core of ARs over 2–5 days compared to a range of [0.1, 0.2] h −1 for R3, R4, and R7 during their late-decay phase. Once again, the rates of decrease exhibited in the large ARs are maintained over periods of days, whereas in the small regions within the CH, the rapid changes occurred in a matter of hours. 5.4. Spatial Distribution of FIP Bias The spatially resolved composition map in Figure 8 , as well as maps in previous studies (e.g., Baker et al. 2013 , 2015 ; Brooks et al. 2015 ), have revealed that FIP bias does vary over spatial scales of a few arcseconds. Patches of higher FIP bias (>2) were found in the core of the EFRs, which is consistent with the Hinode /EIS observations of large ARs in Baker et al. ( 2013 , 2015 ). There was enriched plasma in the vicinity of loops linking the positive polarity of R1 and the negative polarity of R2 (see patches of FIP bias in the range [2, 3] between the mask contours of Figure 8 (b), which spatially correspond to the loops connecting R1 and R2 in Figures 7 (a), (b) and Movie 2). The magnetic field alignment of R1 relative to R2 was favorable for reconnection between the external loops of each region. The reconnecting loops contain already enriched plasma but it is also possible that the Alfvén waves generated by reconnection may have stimulated the enrichment (e.g., Laming 2004 , 2015 ). Finally, the plasma composition within the two largest EFRs had non-Gaussian distributions ranging from photospheric to coronal FIP bias (Figure 9 ). The distributions were mildly skewed toward the higher end of the distributions, with 32%–36% of the pixels within the masked regions exceeding FIP bias = 2. The lower end of the range of FIP bias values was consistent with previous observations of FIP bias in newly emerged loops (Sheeley 1995 , 1996 ; Widing Feldman 2001 ; Laming 2015 ) and with studies of plasma composition in CHs (Feldman et al. 1998 ; Brooks Warren 2011 ; Laming 2015 ), whereas the upper end of the range, ∼3, was lower than the levels typically found in quiescent AR cores, ∼3–4 (e.g., Baker et al. 2015 ; Del Zanna et al. 2015 ). The fraction of pixels containing FIP bias >3 was small in these regions: ∼4% for R1 and ∼1% for R2. The extent to which plasma is enriched is likely to be affected by the CH environment. EFRs are partially or fully surrounded by CH field containing a large reservoir of unmodified photospheric-composition plasma. Interchange reconnection between the closed loops of the EFRs and the open field of the CHs creates pathways for mixing of