package.json currently has aws-appsync hard-coded to 1.3.3 due to issue with aws-mobile-appsync-sdk-js: https://github.com/awslabs/aws-mobile-appsync-sdk-js/issues/233
package.json currently has aws-appsync hard-coded to 1.3.3 due to issue with aws-mobile-appsync-sdk-js:
awslabs/aws-mobile-appsync-sdk-js#233