From their email notification:
"We’re contacting you because you’re using AdSense for Domains to monetize your undeveloped domains. After evaluating the benefits of our partner network, we’ve decided to retire the Hosted domains product within AdSense. Going forward, undeveloped domains will only be served through our existing AdSense for Domains distribution network.
...
March 21: You’ll no longer be able to create new Hosted domains
April 18: Hosted domains will become inactive and it’ll no longer be possible to earn from them
June 27: Hosted domains will no longer be available in AdSense accounts
...
To continue monetizing your undeveloped domains, you can migrate your domain portfolio to any domain parking provider.
...
Please note that this upcoming change won’t affect any other AdSense products you’re currently using or the availability of other products to you. In addition, reporting on your Hosted domains will remain available throughout the schedule above and for a period following the retirement."
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"We’re contacting you because you’re using AdSense for Domains to monetize your undeveloped domains. After evaluating the benefits of our partner network, we’ve decided to retire the Hosted domains product within AdSense. Going forward, undeveloped domains will only be served through our existing AdSense for Domains distribution network.
...
March 21: You’ll no longer be able to create new Hosted domains
April 18: Hosted domains will become inactive and it’ll no longer be possible to earn from them
June 27: Hosted domains will no longer be available in AdSense accounts
...
To continue monetizing your undeveloped domains, you can migrate your domain portfolio to any domain parking provider.
...
Please note that this upcoming change won’t affect any other AdSense products you’re currently using or the availability of other products to you. In addition, reporting on your Hosted domains will remain available throughout the schedule above and for a period following the retirement."
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