Jim Hawkins wrote

One thing that is never mentioned in the official
notices of inflation rates is the level of uncertainty
of the figures.

Yes, I've never noticed anyone doing that world wide in any situation.

It is particularly inportant to know this

Not really when the real problem is that any inflation
number varys much more due to what is measured.

when much is being made of changes as small as 0.1%.

Only by journalists and politicians normally.

I would be surprised if the uncertainty was much lower than 1%,

Its actually much higher than that because of the extreme
variation in the inflation rate of the different components
like cheap stuff from china, food, rents, land, mortgages etc.

but perhaps someone in the know
will take the risk of enlightening us ?

Unlikely that no one does that world wide that I have ever noticed.