I find no shift within the poem.
E.D. may well have come from this illumined space,
yet dressed it finely with situational metaphor & attributes in most of her other work;
that said, this poem possibly expresses her understanding and experience most deeply and directly;
Her Being , freed, delivered these words of Grace.
The poem itself advises slanting truths - in metaphors!
She was revolutionary.
Not in poverty, but in relative solitude caring for an ailing relation
she avoided being pilloried for her honesty and genius.
Ergo: "If you`re going to tell the truth, have one foot ready in the stirrup".(`Quote, Unquote.`I don`t recall whose, sorry.)