The approved dealer wants to keep mine 12 days 
Hi Clare,thanks for caring i’ll be using the one my Dad left me whilst mine will be serviced. x x
Normally the basic service job itself takes anywhere between twenty minutes to an hour or two.
The additional time (up to a month or more in some awkward cases) is to make sure that the watch is keeping good time and to enable fine adjustments to the mechanism and twelve days is a much faster turnaround than many. Many fine quality Swiss watch mechanisms are regulated by the manufacturer for six months to a year before they’re passed as certified chronometers and installed into a watch casing.
Also, as one of the other answers mentioned, the watch could simply be going into a queue for work to be done in which case there is a basic service/cleaning but only a brief check over about twenty-four hours for accuracy.
Another likely possibility is that twelve days allows the approved dealer sufficient turnaround time to send the watch away to a workshop possibly even in another country.
If you are talking about self-winding watches, that may be reasonable, depending on how busy.
Also, it can be hard to find someone to work on those anymore.
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thats a good time scale for watch repair/service.
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he is waiting for parts
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it can be a big job depending on : if parts need replacing – might have to order the parts – watch would have to be put on test first to see the problems or on test after the service to see if the problems are resolved . is it a free service ? What watch brand is it ? How old is the watch ?
These factors all make a differance to duration .
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Normally the basic service job itself takes anywhere between twenty minutes to an hour or two.
The additional time (up to a month or more in some awkward cases) is to make sure that the watch is keeping good time and to enable fine adjustments to the mechanism and twelve days is a much faster turnaround than many. Many fine quality Swiss watch mechanisms are regulated by the manufacturer for six months to a year before they’re passed as certified chronometers and installed into a watch casing.
Also, as one of the other answers mentioned, the watch could simply be going into a queue for work to be done in which case there is a basic service/cleaning but only a brief check over about twenty-four hours for accuracy.
Another likely possibility is that twelve days allows the approved dealer sufficient turnaround time to send the watch away to a workshop possibly even in another country.
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sounds likes its a big job you could get a cheep one while yours is being fixed
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