Different medal

RyuuNoKokoro

Yesterday when I finished my banner I recorded the moment when I got the medal

Before correct medal appear wings medal

Is not a real problem but is a bug.

Have a nice day

iRow

Same here.

kiloecholima

Displayed for me for a split second before switching to the correct medal. This has also happened during events in the past.

Perringaiden

This has been an ongoing bug for many new badges, so I don't think it's related to Second Sunday itself, but rather the popup is simply failing to select the correct image in general.