trurle
Banned
I think the sloreck describe the re-modelling of the city rather than razing. Also, looking on cities with significant Jewish population (like Vilnius) one can see the population decline about 50% from the combined German (eliminating Jews) and Soviet (eliminating Poles) actions. With firm German control, population decline of Vilnius is likely in 25-35% range.How long do you think it would take to raze a single Soviet town or city as you described above?
Answering your question, taking apart a war wreckage and clearing roads typically takes about six months.
Overall, it is meaningless to describe a fate of generic "slavic city". The fate of the any given city was highly dependent on fortunes of war and the national composition. The Warsaw (68% decline) falls on the bad side, Smolensk (25% decline) on the good side, while cities like Vilnius (50% decline) are somewhat on the middle. I`d opt for 30% averaged decline of the population of Slavic cities followed by population rebound if the Germany would be able to control them for ten or more years.