The closest thing I could find, from
Linkory Vtoroj Mirovoj:
The radarstations of the types 281, 284 and 273 was shifted to 281B, 274 and 277 respectively. A radar type 293 was added. Furthermore two radarstations of type 282 and 285 were installed.
Note that the quote is translated by me into english, so it might not be grammaticaly correct, but the data should be(presuming the book isn't wrong, or if I've missunderstood something).