I have found several references to the Signal-post Cottage, between 1817 and 1838 but unsure where it was exactly. The first advert states that it is on the (sand) hills, near Stafford’s Hotel, which later became known as the Vine Hotel. Later adverts were placed by Mr Enderby, who also ran the Vine Hotel after Mr Stafford.
Source: Stamford Mercury 16 May 1817
The following advert was placed in the Stamford Mercury in 1832.