To start, we strongly recommend that you go back to the attorney who drafted the trust or another elder law attorney in the state where your mother lives. The answer to your question may depend on the terms of the trust and on state law. In addition, sometimes either state law or the state’s interpretation of its own laws change over time. To find an attorney near you go here: https://www.elderlawanswers.com/elder-law-attorneys.
That said, if your mother has been receiving the income from the trust, then it appears she has this right under the trust document and that right will continue. She will have to keep receiving the income and report it to Medicaid.
For more information about Medicaid and trusts, click here.