Baseline Hold Off extension: Defines how long the baseline is kept frozen beyond the end of the trapezoid. The baseline hold-off extension is expresssed in steps of 8 sampling periods.
This is the register DPP_BASELINE_HOLD_OFF_EXTENSION (Tblhoe)

Baseline Hold‐Off (0x1n7C (channel n), 0x807C (all channels, write only), R/W, )
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Bit Description
[7:0] Baseline Hold-off extension: Defines how long the baseline is kept
     frozen beyond the end of the trapezoid; after that time, the
    baseline starts to be calculated again but it might take some time
   (depending on the number of samples for the baseline mean) to
  recover. The baseline hold-off extension is expressed in steps of
 the sampling clock unit (10 ns).
[31:8] Reserved