Python: Delete vertices by coordinates

Question

I have a grid of objects like this:

Each object is made of 2 separate meshes (red and blue). Is there a way to use python to delete only the red part and then move the blue part to the front? The red parts' vertices are all Y coordinate 7.5 or bellow so I was wondering if that could be used to select and delete them. The remaining geometry has to be moved -15 along the Y axis afterwards

I can put all the objects in a collection with a specific name or select them manually before hand if that helps make it simpler

Answer 1

   import bpy
   import bmesh

   for object in bpy.context.selected_objects[:]: 
    
    if object.mode == 'OBJECT':
        bm = bmesh.new()
        bm.from_mesh(object.data)
    else:
        bm = bmesh.from_edit_mesh(object.data)


    bm.verts.ensure_lookup_table()
    bm.faces.ensure_lookup_table()

    for vert in bm.verts:
        print(vert.co)
        if vert.co.y <= 7.5:
            bm.verts.remove(vert)
        else:
            vert.co.y += -15

    if object.mode == 'OBJECT':
        bm.to_mesh(object.data)
        bm.free()
    else:
        bmesh.update_edit_mesh(object.data)

1. select all objects which should be affected
2. run the code