https://www.timeanddate.com/sun/portugal/faro?month=5
But according to how the apartment was left ie lamp on in lounge and curtains/shutters closed in children's room I don't see how the outside light influenced anything internally?
The Paynes were on the first floor and had their own hi-tech baby monitor therefore they were not carrying out what to my mind was a bizarre checking arrangement. I don't know the layout of the apartments occupied by the Oldfields and Tanner/O'Brien but if they were similar to McCanns they may well have been walking around the front and listening at the shutters some of the time.
According to KM when GM stopped to speak with Jeremy Wilkins, who was pushing his child around in a buggy, GM discussed their "childcare arrangements". JM was someone GM had known over a matter of days through tennis. So now someone he knew virtually nothing about in terms of character knows his children are home alone! Who else did GM tell about their "childcare arrangements"?
The shutters weren't completely closed, so outside daylight may have made a difference earlier on.
the external blinds closed but with some slats open
https://www.mccannpjfiles.co.uk/PJ/GERRY-MCCANN-10MAY.htmDespite everyone agreeing that the Payne's did no checking, Gerry said;
On Wednesday night, 2 May 2007, as well as he and his wife, he thinks that DP also went to his apartment to confirm that his children were well, not having reported to him any abnormal situation with the children.
Jez Wilkins knew the night before (Wednesday) what the group were doing;
Jeremy and Bridget became aware that although the McCanns had taken up the use of the creche facility during the day, they had not done so for the evening hours and had left the children in the apartment but were checking on them regularly and that other members of the group appeared to be doing the same.
They expressed surprise over this.....
https://www.mccannpjfiles.co.uk/PJ/JEREMY_BRIGET.htm