If a company moves its office from one location to another in the same city, is distance a factor? What kind of timeframe must we provide if we are doing this?

Usually, a move within the same city would not be significant enough to cause problem. As such, specific notice may not be required. The change can just be implemented. In some extreme circumstances, the move may be an issue (if, for example, it would make it very difficult for an employee to get to the new location). I propose that you call me to discuss this more specifically.