At 19:58 22 November 2018, Ross wrote:
There are a couple of Janus flying round in France somewhere
that as far as
I am aware are allowed to go to 18,000 hours. 12,000 hour
check done,
extended for another 6,000. Not bad value for money if you
intend on flying
a lot

As far as the tc-holder is concerned the max is 12000 hours for
any Schempp-Hirth glider. I would say you have the 18000
confused with the ASK-21 which is the only German built GFRP
glider certified for more than 12000 hours currently.