We want to update our apps as soon as possible, before May 25th.
If the NPA flag is already available and usable now, adding support for it now gives us the ability to start rolling out updates.
In the other forum post you said you had implemented this AdRequest configuration already (https://forums.coronalabs.com/topic/72096-gdpr-compliance/page-6?hl=gdpr).
Hence, if it is already implemented, and it works with your current AdMob version, please roll it out.