how long do you guys let the silicone dry for before grouting?

For me i usually silicone last and tell them 24 hrs. However if i am sealing in a bath or shower before tiling it does nt matter

I do normally but tomorrow got a bit of a rush on, got to finish tiling,only 4 sq meters left, (customer didn't order enough tiles been waiting for them coming from spain) grout it and silicone it all tomorrow, too far away to slicone it day after(22 miles 1hr driving to get there)
so i was going to silicone joints 1st thing in morning, finish tiling, have early lunch, then grout?! will silicone be dry enough in 4 hrs?

Technically i would say no(normally only a skin would be formed). But there may be something out there that will.

Why not finish grout clean up then silicone and let your customer know it takes 24hr as does grout?

I agree with Bigandy. Grout first as it will get to a state of dryness to allow siliconing quicker than waiting for the silicone to set. it is way too easy to make a mess of silicone when it is not fully set. I know because I have done it!

mapei ultra colour and ardex gk grouts are rapid setting this may help in this situation

I tell my customers not to touch the tiles/grout/silicone for 24 hours. I lay it on, and never had a callback.

Obviously if you are on a larger job for many weeks then I always silicone before grouting makes it easier with no dust around, but if you are pushed for time and travel then always grout first then silicone.