I personally have not noticed a change but have heard of others who have had their sites get back some good positions.
I have noticed the last while that Google almost seems to have different algo's for different real estate market areas. I have sites that target the SE differently using different optimization and in some areas one will work and other areas others will work. The same optimization does not necessarily seem to work everywhere.
Granted, there would be differences due to competition etc. but I am thinking this may go beyond that. It has been stated by Google that they change their ranking criteria several times a month and maybe they are mixing things up as well just to confuse.
Of course, lots of good inbound links still help a site ride out the changes.
One of these days Google will notice users are no longer as loyal as they once were and they will notice their market share going down - and then they will give their head a shake and stop this nonsense.
As much as I have been a beneficiary of their algo changes I would like to see them back giving more relevent results. I will benefit from that too

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