Hey Lee-
I was a hydraulic fracturing engineering for Schlumberger out of college. I also worked for a water treatment company developing technology to clean fracking flowback fluids for reuse at the well location - a much needed technology considering how much water is used in fracking operations.
Generally, operators expect to recover about 20% of the pumped fluids for reuse or disposal. Right now, injection is the most common disposal method, but as I mentioned, many companies are trying to reuse this fluid. This flowback as one big advantage - low dissolved solids (TDS) like salts, which high levels of can cause problems with the gel the operators pump during the frack.
Timeframe really depends on flowrate. Operators will watch TDS levels of the water and when they see a rise, it means they're starting to pull formation water rather than flowback. Typically though, it's usually 3-7 days depending on the size of the frack.
With shale oil and gas, horizontal wells, operators are fracking in multiple stages - 20 stages or more. The horizontal section can extend for a thousand feet or more depending on the size of the pay zone, where the oil / gas is trapped, etc. Operators will frack the first stage at the end of the horizontal, move the workstring up the horiztonal, set a plug (so they don't frack a stage they already did), and frack the next. No production occurs until all stages are fracked, the plugs are drilled out, the production pipe is installed, and a number of other less time-intensive steps.
Fracking is a 24/7 operation. It doesn't take long in between stages. A frack company could be on location for a week or more, especially if they are fracking multiple wells on the same well pad. I've seen up to 16 wells on the same pad.