Kitchen Skylight Damp Patches

[lexio7]

Hello

I have recently had 2 skylights installed in my dining kitchen area.

The plastering is complete and I am seeing damp patches on both windows in the lower corners on both windows.

It is not raining outside at the moment, but it is very cold.

The day before we had very heavy rain for almost 2 days and there were no damp patches during the rain.

So I am wondering if these patches are condensation or leaks.

Any insight is much appreciated.

Thanks