Hello Falco, welcome to the Forum, and congratulations on your new Salisbury. Don't worry, this is the right place to post.
NiMh batteries are best when used to empty, but that's not important every time, as long as you use to empty or nearly so occasionally, say one in ten times they last a long time.
Once the charger light goes green, the battery is fully charged and can be unplugged. Subsequent charges like this are normally much shorter than theory indicates, since there's still quite a lot in the battery despite it seeming to be fairly empty on the bike. The bike will cut usage while the battery still has around 1.1 volts in each cell to protect them from excess discharge.
Basically, just use and enjoy, and rest happy in the knowledge that Powacycle's replacement batteries are by far the cheapest on the market.
Many of us buy them to use the insides to recell other batteries or to use as backup batteries on other bikes.
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