Megan Scenic 1.9 RTD - windscreen wipers parking vertically, why?

[H]

Hi, I'm looking for help on my '98 Megan Scenic 1.9RTD.

The windscreen was replaced at the weekend. When the guys started work the
windscreen wipers were in the normal 'parked' position - and were in the
same position when they finished.

On Tuesday we drove in the rain for the first time since the windscreen was
replaced.

The wipers did not move from the 'parked' position when the car was started
nor during the first part of the drive in the dry.

However... when it began to rain and wipers were turned on they did not wipe
quite so far to the right as normal, yet appeared to knock a bit harder
against the scuttle. When they were turned off, or intermittent mode used,
they 'parked in an upright position to the right (as viewed from driving
seat).

I first thought that the repair guys had replaced the wipers in the wrong
position on the spline - but that doesn't make sense.

If they had done that then the wipers, I would have thought, would wipe
further to the right and 'park' on the left but higher up - if you see what
I mean.

So, anyone any idea of what might have happened.... and how to fix it?

Thanks,

Hal.