IRA left to beneficiary’s living trust

IRA Owner dies and leaves money to the grantor trust of his non-EDB beneficiary.

If this trust is irrevocable (but still grantor), does it qualify for the 10-year rule? An irrevocable grantor trust seems to meet all of the qualifications of a qualified/see-through trust as IRA beneficiary.

If the trust is revocable, does it fail as a qualified trust and get stuck with the 5-year rule?

If so, could the bene dissolve the trust before the beneficiary determination date and let the account flow to her name directly, getting her the 10-year term? Or would dissolution of the trust (the named beneficiary of the IRA) cause that beneficiary to fail and move to whatever contingent is listed?

Please and thanks.