Diesel Benz
MB Enthusiast
There is absolutely no requirement to tie an update in with a service. Whilst that may be beneficial to the dealer the update is a stand alone item which a car less than 3 years old is entitled to unconditionally. My car was updated twice last year. Read your handbook, everything you need to know is in there. Bear in mind the update process can take most of the day.
I have to admit that I have not read the car manual thoroughly but I don't think the update rules are mentioned there in detail.
Some time ago I did print a couple of documents. One stating that two updates per year are allowed. I would need more time to find this document (must have been either from WIS or from TIPS).
I did find another document that talks about updates during a service visit and a separate paragraph on updates between services. The charging rules should be the same for both cases.
The internet site mentioned in the document is way outdated, typical for MB.
Updates take a lot of time, specifically for the older cars (that still have free updates for the 3 first years) which makes workshops reluctant to follow the instructions from the headquarters.