So at 17 weeks I would expect a normal A time when well-rested to be around 1h45-2h. After a short nap you would anticipate it (for most babies) to be reduced, but I wouldn't tend to go much shorter than 1h30 at this age. The danger with putting him down again too soon is he has another short or broken nap and then ends up really OT by the end of the day. It's not an exact science and some babies will display good tired cues that you can follow, but others won't and it just takes a bit of experimenting. Sorry that's a bit vague!
