Very nice mules, but a size too big

I wanted this Birkenstock as comfortable Hauspantoletten. I have looked at the size chart and as the mules should have fit into size 42 accordingly (I always wear 42). But unfortunately, after the super-fast delivery, I realized that are too long, 1 cm remained behind at the heel free.

On the other hand I had. A little concerned about the footbed, due to the vaults, I sinking and spreading feet, but zero problem, on the contrary, I was surprised how very comfortable I was in your shoes (Normal size)

These mules do I return now and got immediately ordered other Birkenstock Mules Series "Madrid", this time in size 41, I hope that I fit these. However, in a different color, which was black with pink sole just already been a blast, now I have ordered Toffeebraun, I want to go to a play it safe, that I may return for free, if I will not fit the 41, which I hope will not happen. And the color, in the end, this is not so important, the main thing convenient.

Addendum:

Rescission of the purchase of the black mules is super fast and takes place has ended, the Birkenstock Madrid in Brown (toffee), size 41 came the next day, fit perfekt- and I like really good!