Does this signify anything as far as the development industry is concerned? These are the next lowrise lots to the south of the activity further north.
The properties were for sale and probably bought by a new owner who wishes to re-establish them as separate properties.
That is all merely a guess based on previous experience when someone buys adjacent properties and don't realize they merge in title and then have to go to C of A when they want to sell one of them.
I walk past these two houses every day, they were both designed by E. J. Lennox and both are designated. They were upscale bed & breakfasts ("Cawthra Square Inn") run by a couple for years who finally wanted out. They listed both homes about 3 years ago but they didn't sell and were taken off the market. They tried again the next year at reduced selling prices and 514 (The Rundle House) sold to some music organization, I think it's for young people who live there and they have a lot of parties at night. I don't know what happened with 512 (Edward Gallow House) but it sits with furniture, unused.