However, you need to watch out for your height
lose, from where you are released to where you land. If it's over
1000m (I think that's the value) you have to fly further. So, if you
are on a hill-top site and land in the lowlands it can be an issue.

I'm pretty certain it's 1%, i.e. 500 metres (work on 1500 ft and you'll
be fine). So if you take a 2,000 ft tow (600 metres), climb straight off
tow and land at the same altitude as your launch airfield, you have to
fly 60 km. In other words, your height loss must be no more than 1% of
the straight line distance, and the flight must be over 50 km.

Height loss is measured from your lowest point immediately after
release (or tug pilot certification of release height if there's no low
point), so one option is to find a thermal, open airbrakes, descend to
whatever height you've worked out you need, and then climb back up.

You need a barograph to record that you made the flight without landing
half way and taking another launch, and that barograph will also record
your lowest point after release.