For those having trouble finding the puzzle during the night hours, make a note of the web address in my @3 and just increase the final digit by one.
For example, this week it's....
https://observer.co.uk/puzzles/everyman/article/everyman-no-4125
and next week it will be...
https://observer.co.uk/puzzles/everyman/article/everyman-no-4126
You can also click on any of the previous Observer Everyman puzzles and, about 3 inches underneath the grid on the LHS, you'll see written Puzzles Everyman (on the same level as 'Downoad the PDF), then, if you click on Everyman you should get the the latest one.
PS. My solutions have also disappeared from last night but, like Jono, I'd already submitted my entry so didn't have to do it all again.