Got this:
Upcoming Google Mobile Ads SDK version sunset
“Please update your Google Mobile Ads SDK to the latest version to avoid revenue impact”
Any information on this and how important it is to update older apps (3 years +) build with Solar 2D using admob?
Any help welcome!
Thank you!
Yup - same here. Email from Google yesterday copied below. I’m always dismayed to get these emails. Still, any news on what the latest SDK is and when it’s due for an update?
Just to say, my app was last updated March 2022.
"
Upcoming Google Mobile Ads SDK version sunset
Please update your Google Mobile Ads SDK to the latest version to avoid revenue impact
Dear AdMob Developer,
You are receiving this email because you have AdMob traffic currently running on versions of the Google Mobile SDK that are slated to sunset on June 30th, 2023. Per the Google Ads Developer Blog announcement in April, we plan to sunset major version v19 on Android and major version v7 on iOS.
What does this mean?
Starting June 30th, 2023, you may notice some disruptions in your ad serving on sunset SDK versions (major version v19 on Android and major version v7 on iOS). Moving forward, ad serving using a sunset SDK version may be reviewed and disabled after this date. Therefore, ad traffic from sunset SDK versions will be at risk of receiving automatic no fills due to stopped ad serving. Additionally, sunset SDK versions will be marked “Outdated” on the Google Play SDK Index, requiring you to update to a supported version for future releases of your Android apps. See this article to understand issues with your app’s third-party SDK for more information.
To avoid disruptions in ad serving, we highly recommend updating your SDK version to the most recent version of the Google Mobile Ads SDK.
How can I update my SDK version?
Please see the Android migration guide or iOS migration guide for more information on how to update.
Why should I do this?
To avoid disruption in ad serving, we recommend updating your SDK to the latest version. In addition, updating your Google Mobile Ads SDK on iOS to version 8.3 and above will provide you access to the same app key. For AdMob publishers, we’ve seen an average of 31% ad revenue lift on iOS – where the Identifier for Advertisers, or IDFA is absent – from app developers who have adopted the Google Mobile Ads SDK 8.3 or later version.
Yours sincerely,
The Google AdMob Team
"
Just to chime in again - ideally I’d like to do an update on iOS with the very latest AdMob SDK incorporated into Solar2D. This would allow those of us not actively updating apps to delay for as long as possible a future update when the next AdMob sunset email arrives.
Thanks very much! 
I would suggest rebuilding your app, I don’t know the specifics version numbers but iOS and Android( I think Android is 21.x) but they were updated to the latest on Feb 6 of this year.
Edit: I don’t have eta for when it would be updated again but it is a good amount of work to update these libs(primarily on iOS). I would imagine/guess probably in later this year(I.e Q3/Q4)
Thx for the feedback!
Thanks for letting is know Scott!