Has the configuration to enable multiple emails to PURCHASING changed?

Summary:

Multiple email address's within PURCHASING Communication Method is failing for our business, has the configuration to enable multiple emails failed? Historically when enabling this feature the rule was to add additional email addresses using a coma (,) with no spaces. Furthermore, to also ensure this feature worked the CONTACT should not be mapped to the ADDRESS on the PURCHASING Site. This set up has worked for a number of years, however since roughly around the time of adopting 25C only the first email address is receiving the purchase order. What has changed please?