700' GFCI Protected Circuit

[glene77is]

Perhaps, but it is lowering the headroom before a trip.

Would the amount of current used by load change the capacitance?

iWire,

(1) Important consideration,
since the 'real' trip point is somewhat unpredictable.

(2) I really think you may be referring to this activity:
(Not 'Change', but 'Charge' the capacitance.)

The Momentary charging flow has a e = Xt phase offset,
on a 'charge curve',
Thus
the 'hot' wire current at an instant
is different from
the 'neutral' wire current at the same instant.
This is during the time period 'under the charge curve'.

I really think you may be referring to this activity.

(3) I like the new avatar. Very "Manly". IMHO.