explain R4 vs R4B

README.md

@@ -6,3 +6,4 @@ formal publication - https://johnmoehrke.github.io/RelatedPersonConsent
 
 ci-build - http://build.fhir.org/ig/JohnMoehrke/RelatedPersonConsent/branches/main/index.html
 
+Note: Building with R4 will produce Errors in the QA. These errors are caused by problems with the Consent specifcation in FHIR core R4. These problems were corrected in the R4B technical-corrections release. So would be best to build with R4B simply to not get the errors. There is no other reliance on R4B, R4 is fine. However at the time of the release R4B was not building proper, gave me three errors indicating that the version 4.3.0 was not valid.