Koko ni okitt panashi ni shicha dame deshoo.
置くき、 oku kippanashi, Japanese think this ku ki is bothersome to pronounce, so you can say okitt panashi. tt is same to the sound of students.
殻 means a cover, noun. so please write it in hiragana because this is a particle. (I think, sorry I am not sure very much)
I can read this as:
You're going to visit Europe on 17th of the month and you're going to stay for a while after that.
And you want to say that you'll be there in Europe at least after 17th.