Hi Mark,
I don`t if you have this Squawk (7003) but i had an alert today and low and behold abvout 30 secs later over came the Red Arrows(its their transit code).Nice to see on the RB,but even better,or a bonus when they shoot past at about 2000ft.Just popped those codes into Airframes.Org and they both come back as from Mozambique,no aircraft details, just their country of origin.
Regards Terry.