Opponents of 235 homes on 72 acres of farmland are urging supporters to write to councillors now.
Mid Sussex District Council Planning Committee is expect to vote on the application for Borde Hill’s estate’s Penland Farm at its meeting on Thursday February 6.
Councillors will meet at 2pm at the district council offices at Oaklands in Haywards Heath.
On a flyer now being delivered to residents, the Penland Road Action Group says: “It is a difficult time of day, we know, but public attendance is vital. Let’s see if we can spill outside of the room.”
The flyer urges: “We know that many of you will have written to our Town Council, but it is now vital that you register your objection to the DISTRICT PLANNING COMMITTEE before this meeting.
“The District Councillors for planning DO NOT LIVE IN HAYWARDS HEATH. We need to tell them how it will affect us.”
More info is on the group’s website at www.penlandfarm.co.uk where the meeting date will be revised if it is changed, or contact Isobel Holloway on 01444 414502.
Trustees of Borde Hill Estate and its development partner Catesby Estates believe there is a need for more housing in the area.
They say ancient woodland will be kept and residents will be able to walk to town. The plans include a roundabout at the junction of Hanlye Lane and Balcombe Road.