CH 2004 AE 1 yellow easter wishes German, letter C6, real run

Switzerland 2004 campaign labels, yellow easter wishes - self-adhesive label,
AE1, Easter Greetings German "Da war jemand schneller als der Hase. Wir wünsche frohe Ostern - DIE POST",
A-PRIORITY Gültig am 07.04.2004, letter with label, format C6 with address and coding line, real run, arrival cancellation on the back 5620 Bremgarten 08.04.2004,
(SBK AE 1, Michel -)

Hints:
On April 6, 2004, Swiss Post published full-page advertisements in various Swiss daily newspapers that on April 7, 2004, it would send 5 free A Mail letters in C6 format up to 100 grams as a gift to customers if they handed them in personally at the counter. This post was provided with a self-adhesive label that was only used on 04/07/04.