That won't matter. 6.8.X should work fine.
The 6.9.x LDM series is a feature upgrade
compared to 6.8...with a few bugfixes as
well. But I'd still recommend you upgrade...
it offers some nice backup features for you
so you know when the feed goes down.
i'm aware, however stability in 6.8.x is actually
better, and i have had multiple alerts for feed
outages for years :)
what is revolutionary to one etc..