This was due to a change in the campaign url query parameters in the campaign config (https://donate.wikimedia.org/w/index.php?title=MediaWiki%3AAppsCampaignConfig.json&diff=39950&oldid=39789). This has since been reverted, so we should start collecting those IDs from these versions again.

Android sends the campaign ID value (JP_2024_05) for metrics instead of utm_source, so iOS could consider switching to that for consistency, if the backend teams are good with that @SNowick_WMF.

Thanks @Tsevener I am able to pull all JP camapign ids as-is, maybe it makes sense to change the iOS format to match Android for ES campaigns? Do you mean we need to check/verify with Fundraising backend team?

@SNowick_WMF yeah, we'll need to do a client-side change and confirm with Fundraising Tech how we should pull and send the ID. We also send this ID to their submitPayment endpoint (in addition to MEP), so it could affect some of their stuff as well. This is captured in T367360.

@SNowick_WMF could you confirm that you aren't seeing issues anymore? And if so, close this one out. Thanks!

Verifying we are no longer seeing impression events in app_donor_experience without campaign_id values in action_data for any events beyond app version 7.5.2.3622. Closing this ticket as resolved.
Data.