How long will tubes last in a pre-amp?


My Sonic frontiers Line One seems fine, tho I haven't put anything else in place of it to test.

It is a decade or more old.  Should I get worried about the tubes?
randy-11
In my ARC REF 3SE I replaced all the small tubes by 6H30P-DR ,
they should last more than 10.000 hrs.
Why not replace them? Preamp tubes are inexpensive. Ten years of use with any tube will wear down!
Every pre- amp is different usually 5 to 10 thousand hours but it depends on the voltage they run at.
I am still considering the CJ classic 2 SE Preamp

just not sure about having a tube. S is so much easier.