Difference in memory allocation between AMQ 7.9 and AMQ 7.10

Issue

When broker starts in a pod the following messages are logged in console log:
AM 7.9

AMQ221057: Global Max Size is being adjusted to 1/2 of the JVM max size (-Xmx). being defined as 1,342,177,280

AMQ 7.10

AMQ221057: Global Max Size is being adjusted to 1/2 of the JVM max size (-Xmx). being defined as 671,088,640

Since an identical broker's CR is used in both cases, what would be the reason for the above discrepancy