It very much depends on the dealership and the 'relationship' you have with them.
Bought my MCC from a dealer I'd never had anything to do with before who have a high volume of cars going through (both Mini & BMW) and they offered a 3 day turnaround - as it was I couldn't collect it until a week later anyway.
On the flip side when I bought my Boxster they received the car at 12:15pm, PDI'd it, fitted tracker, valet etc. and I drove it off the forecourt at 6pm - but they are a much lower volume outfit and they had 'lost' the car in transit at one stage so owed me some flexibility.
Bought my MCC from a dealer I'd never had anything to do with before who have a high volume of cars going through (both Mini & BMW) and they offered a 3 day turnaround - as it was I couldn't collect it until a week later anyway.
On the flip side when I bought my Boxster they received the car at 12:15pm, PDI'd it, fitted tracker, valet etc. and I drove it off the forecourt at 6pm - but they are a much lower volume outfit and they had 'lost' the car in transit at one stage so owed me some flexibility.