According to here,
https://support.google.com/analytics/answer/11583528?hl=zh-Hans&sjid=3641647078283548203-AP#
UA must be updated to GA4 properties. I'm using measurement protocol to send data to GAU properties. So in order to send measurement protocol to GA4 property should I update my existing measurement protocol apps?
Our program is self-service by users, there is no way to update it so is there any way i can complete this upgrade
Yes you will need to use the Measurement protocol for Ga4 your app using the old measurment protocol for UA will not be able to send data to a GA4 acccount.
You may want to have a look at the Measurement protocol for Ga4 before you begin. Currently it is very limited and does not allow you to send all of the events and hits that are sent via the official sdk's. You may not be able to recreate what you are doing with UA with this new version.
They are still working on it though.
