The Illinois Notice Of Right To Petition For Construction Of The Terms Of Testamentary Trust is a form that must be served on beneficiaries of a trust to inform them of their right to seek a court-ordered interpretation of the terms of the trust. The form must be served within 60 days of the trust becoming irrevocable. The notice informs beneficiaries that they have the right to petition the court to construe the terms of the trust, and sets out the deadline for filing the petition and other relevant information. It also provides information about the trust, such as the name of the settler and the date on which the trust became irrevocable. There are two types of Illinois Notice Of Right To Petition For Construction Of The Terms Of Testamentary Trust: a single-beneficiary notice and a multiple-beneficiary notice. The single-beneficiary notice is used when the trust only has one beneficiary, while the multiple-beneficiary notice is used when the trust has more than one beneficiary.