With the Canon TS-E 90mm f/2.8L
and 135mm f/4L Tilt-Shift Macro Lenses
I took a fresh look at the site's How to Determine the Age of a Canon Lens
The answers in the serial number table lookup appear to be plausible for both lenses.
So, I added the new year to the chart.
If you have acquired a new Canon lens in the last year or so, please take a moment to look up its date of manufacture
Then let us know if the answer appears to be correct for your lens.
Or, at least approximately so as a few months of difference in the age of a lens is usually completely irrelevant unless there is a service notice issued and in that case, specific serial number ranges are provided.