In the US, it depends on too many factors to pin down precisely. The best Readers can give you are VERY broad estimates based on their own experiences.
Repairs done in my fairly large store when parts are already on hand and there is not a big backlog typically take three days elapsed time. if any of the preconditions are not satisfied, or anything happens to derail the process it will take longer.
Repairs sent to a repair depot when parts are already on hand at the depot will take at least seven to ten days, because there is a lot of waiting for courier time in there, and two weekends when nothing moves around at all. (An estimate of three to five days Instantly becomes at least a week of elapsed time if it includes any part of a weekend.)
Your results WILL be different.
Tracking of the actual progress of the repairs are abysmal. You will have no accurate idea of repairs status until they contact you to come get it.
Remember that in the papers you sign to allow the repair is a promise that you HAVE good backups on hand, and Apple does NOT promise to return your files intact. if something goes wrong, they could have to replace your drive. You MUST have a trusted backup before you submit your Mac for service.