I continue to be amazed at how many local councils fail to meet their statutory obligations, and completely ignore requirements (and good sense) in terms of open government and accountability.
Parish Councils are required to publish the agenda of forthcoming meetings 3 clear days in advance of the meeting. The Transparency Code confirms that as well as the agenda, associated meeting papers should also be published, and that this should be via the council’s website.
The Freedom of information Act gives the public a general right of access to all types of recorded information held by public authorities (which includes Parish Councils), subject to certain stated exceptions. I suggest that you submit a Freedom of Information request to your parish council for the document you want to see.
A speedier route might be to ask the Local Planning Authority involved. They may be more on the ball in terms of openness etc. Certainly my local planning authority publishes on its website. submissions and comments received in respect of planning applications (and similarly a freedom of information request to them should elicit the document you want to see).