The Martha’s Vineyard Commission last week moved forward on a four-lot subdivision off Middle Line Road in Chilmark, and continued a hearing on a second subdivision plan for the Quansoo area.

Public hearings were held on both plans last Thursday. Both are developments of regional impact because they involve more than 10 acres and the division of habitat for state-listed species.

A proposal by the Eileen S. Mayhew Revocable Trust for a four-lot subdivision calls for up to three new houses and three guest houses off Middle Line Road. About seven acres with space for a trail would be sold to the Martha’s Vineyard Land Bank.

The plan was filed under the town’s flexible siting bylaw, which allows owners to reduce the lot size to under three acres, as long as the plan includes enough open space to make up the difference.

The National Heritage and Endangered Species Program has signed off on the plan. The Chilmark planning board has also shown support for the project.

“There’s not too many issues with this one,” commission DRI coordinator Paul Foley said in a staff report.

The commission decided to bypass the usual post hearing review by the land use planning committee and moved on to a delibration, scheduled for this Thursday.

In the second plan, Chilmark resident David Damroth is proposing a four-lot subdivision off Oyster Lane, including a one-acre youth lot, with a total of up to three main houses and one guest house. A house and a workshop already stand on the site.

The existing lot lines resulted from a subdivision in 1987, which included a covenant that 100-foot buffers be maintained along the protected byways that border two sides of the property. The new plan calls for a 100-foot buffer along one path and a 25-foot buffer along the other, leading to some concern from neighbors.

Mr. Damroth is seeking a special permit from the town board of appeals for the youth lot, which would require that the lot remain affordable for 10 years. He said the future owner would be open to a 15-year restriction.

Commissioners asked Mr. Damroth to return with proposed building envelopes and more information related to the buffer zones. The hearing was continued to this Thursday.