[3] On 7 December 2008, Mar Meelis was elevated to the rank of Metropolitan of Australia, New Zealand and Lebanon, taking the honorific His Beatitude in place of the earlier His Grace.

The event drew close to 3,700 people at the St. Hurmizd Assyrian Cathedral, Greenfield Park in Sydney, Australia.

Since his arrival, as Bishop of the Diocese of Australia and New Zealand, Mar Meelis has expanded and contributed to the growth of the Church and its activities, which has steadily improved the Assyrian communities in both countries.

In recent times, he played an important part in raising funds from others for the construction of classrooms and an administration facility for a primary school.

In 2018, announcements were made for the establishment of another primary school in Sydney's Cecil Park, next door to Saints Peter and Paul Church.

In early 2019, Mar Meelis held a third meeting to discuss the establishment and academic teaching commencement of the Nisibis Assyrian Theological College in Sydney, during which a Dean was appointed.

This conflict also caused a split in the Australian branch of the AUA (based on the Church factions), and led to inter-communal rivalry between the Nineveh Club and the Assyrian Sports and Cultural Club, which aligned itself with the Old Calendar faction of the Church of the East and began its own Nisibin Assyrian School.

In 2017, churchgoer Sargon Eshow, who established a denunciation against Mar Meelis on Facebook, was ordered to pay $150,000 in damages after the religious leader sued him for calumny in the NSW Supreme Court.

Eshow was suspended from the church for two years from April 2015, after making a couple of posts on his Facebook page in Arabic derisively criticizing the bishop.