From experience, it depends on how much content I'm making for the month and what my workflow is. For art, I can animate about 3 scenes a month with a week left for coding (adding the scenes in and setting up events). Adding in new mechanics usually takes more time (a week or two). Writing scenes usually take a bit over a week. The testing phase ranges from a couple days to a week, depending on how many bugs there are to fix.
Judging from how much time this update is taking, I say Bones has a lot ready for everyone to play with. But then again, I'm only judging this based on my workflow.