Question on Sociable Lapwing: Migration and Nesting

After a failure in 2019 to see the Sociable Lapwing in Kazakhstan, then 2 years of Covid, I found Alexandre Fedulin in Korgalzhyn in 2022 with the hope of observing this bird which has unfortunately become very rare.

I was incredibly lucky because after 3 days of fruitless research, thanks to the perseverance and experience of Alexandre we found a flight of 160 Sociable Lapwing in front of us at the edge of a small lake.
We were able to observe them all day long, we stayed at a distance so as not to disturb them despite a herd of sheep, a shepherd on a motorbike, a fisherman who came to lift his nets, the Lapwings remained on site and in the afternoon they came 25m from our car.


However, I now have questions to which I have no answer.
We made this observation on June 7, the next day they had disappeared from the scene and continued their flight. I have read that Sociable Lapwings nest from late April to mid May and that the young fly from mid June to early July.
Looking closely at these birds I found, except to be mistaken, that they were all adults in breeding plumage and that there were therefore no young of the year in this group of 160 birds.
For Alexandre, these are adult Sociable Lapwings migrating to the nest.


I would like to have confirmation that this group of birds corresponds to a migrating flight leaving to nest in northern Kazakhstan or in Russia and where precisely. But I wonder because I think it's very late to go nest when it was already June 7th.
I know and appreciate the ''birds.kz'' site so I allow myself to ask my question on this site and hope that scientists and specialist ornithologists, if they read me, will be able to provide an answer to my questions based on a series of photos that I attached.
I would also like to say the pleasure as a Frenchman is that I have to share this experience with the ornithologists of Kazakhstan and to be able to testify to the existence of the Sociable Lapwing with a significant group of 160 individuals.


Thank you in advance to anyone who will take the time to read and respond.
Jean Paul Roux

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