My Tyres were advertising Barum Tyres, So sent email to ask the age of Tyres.

As you know My Tyres is an EU company in Germany.

Answer to my email about caravan tyres

Thank you very much for your interest in us.

We would like to inform you that we consider as being new all the tyres that have been manufactured during the last 2 years. Since the tyres in your order are shipped directly from various warehouses all around Europe according to availability, we are unable to ascertain the DOT number of a specific tyre due to the limitations of our system.

Please note that during ordinary storage over the course of time, the specific characteristics of the material may improve, since the rubber mixture is not immediately subjected to the stresses of driving, and so it may further harden. According to BRV (the German Tire Retail and Vulcanization Trade Association e.V.), tyres stored properly for up to three years are considered factory-new, and up to five years are considered new.

We would recommend that you check our Home page where you would be able to find the option " Production year 2023 guaranteed " and check if your required tyres are offered here.

If you have further questions or concerns, simply send us an email or call us.
With regards,

Our 2005 troll was laid up for most of its life, the wheels were removed and stored in a dark and cool place for many years. I had them changed once we got the van on the road and the place that fitted the new tyres, said that the original tyres were in great condition.
I gave them to a mate, who used them on his Citreon Berlingo van. He's still using them now.

I used My Tyres to replace the Barum tyres on my van for new Barums, I paid a small extra charge for 2022 manufacture,
they arrived with 23/22 date stamped into them, they were less than a month old.
The 5 year old tyres removed looked to be in good condition, when removed there were obvious bulges inside the tyres
and they had had to have massive amounts of balance weights a few months earlier. Appearance can be very misleading.

Barum is apparently a subsidiary of Continental. Continental produce the Conti Vanco (various types) which are much more available in the uk and would appear to be the same tyre. When I checked with the supplier (local F1 Autocentre) they said they should be fresh as they sell lots of these for vans, but if the date was too old I could reject them. The dates were about 3 months old when I bought mine.
I got a couple of spare wheels and kept two of my originals which I use over the winter or during long storage periods, and keep the road wheels in the garage out of the sun.

This was December 2021 Colin. I think it helped that the fitter was also a caravanner so was aware of the issue.
Another advantage of having a spare set of wheels is that you can shove them in the boot to get new tyres. Handy if you are out in the sticks.