As a patent agent or intellectual property consultant, I believe that when you contact the patent applicant, you must be asked by the customer: how long will it take for the patent to be authorized?
You say: the invention is generally about 3 years, and the utility model is generally 7-14 months, and the time of specific cases will vary.
The customer will be surprised! It's going to take so long? If the customer applied for a patent in the early years, it would be said that the utility model was not very fast, and could be authorized about half a year.
You didn't see the official reply before. It was a little bit false after being questioned by the customer. Now the State Intellectual Property Office replies to the authorization time of three patent types.

December 1, 2020，Consultant No. 310 of the State Intellectual Property Office answered the question on the authorization time of invention, utility model and design

Under the condition of Patent Law：Invention patent applications can be authorized in about 3 years on average
The average time of utility model patent application is about one year
The average time of design patent application is about 0.5 years

When the patent for utility model can be authorized about 1 year, and the relevant issues of patent authorization will continue to be found on the official website of the State Administration of knowledge.

March 25, 2019，Consultant No. 210 of the State Intellectual Property Office replied: how long does it take from the date of application to the time limit for authorization?
Limited by the number of applications, the writing standard of application materials and many other factors, utility model patent applications can be authorized in about 0.5 to 1 year under the conditions of patent law.
From about the first half of 2019, the authorization time of utility model patents will be extended. At the same time, the State Intellectual Property Protection Bureau will also set up intellectual property protection centers in the Department cities. Patents in the relevant fields can go through the preliminary examination channel of the intellectual property protection center to speed up the authorization time.

November 25, 2018，When consultant No. 210 of the State Intellectual Property Bureau answered the relevant questions, the application for utility model patent generally took about 0.5 to 1.5 years.

At present, the way to speed up patent authorization is priority examination and rapid pre examination, but not all patents can be accelerated. Priority examination has requirements for the technical field. Rapid pre examination can only be carried out in the place where there is a local intellectual property protection center, and the patent field should be consistent with the pre examination field of the protection center There is also a squeeze on the cases, and the preliminary examiners are working overtime.
Source: intellectual property rights in progress