On version 9.30 (or newer) of Email to Case Premium, you do not see recipient information in the 'from' or 'to' fields in the inbound case comments on the Timeline.

Starting in version 9.30, Vicasso implemented stricter enforcement of the 'Show Recipients at the Top of Comments from Inbound Emails' feature. To resolve the issue, ensure that the 'Show Recipients at the Top of Comments from Inbound Emails' setting within your Email to Case Premium Inbound settings is enabled.