I spoke to an agent via chat and mentioned some sellers had already received a follow-up email and had been refunded the difference.

The agent told me that they had not issued any refunds to any sellers, and that the issue was ongoing. He said I had to wait a few days to receive the update via email.

Was also advised to hold off sending parcels until the issue was resolved. How on earth can that be good advice, buyers don't want their parcels arriving late, and I don't want any defects for not posting on time.