Aの試作日程の件ですが、Aに使用するBが特殊品かつ輸入品になり、更にAが在庫切れになっている状況でして、当初ご連絡した8月24日に製品が間に合わないことがわかりました。誠に申し訳ございません。
日程を9月の11日~15日に再調整させていただきたいので、ご都合のよい日程を教えていただきたく存じます。いただいた日程にInvitation letterも訂正して提出致します。この度は私の勉強不足により、ご迷惑をお掛けしてしまい誠に申し訳ございません。
I would like to rearrange the schedule in the period during September 11th to 15th. Would you please tell me your availability? I will revise the Invitation letter with the new date and submit it.
I would like to apology for inconvenience this may cause due to my lack of knowledge.
As we would like to arrange the schedule on September 11th to 15th, please let us know your convenient date. We will edit the date which you inform to us on the invitation letter and will submit it again. We are really sorry for having caused a lot of inconvenience to you due to the lack of my research.
We would like to to change the date during 11~15 September. Could you please tell us your convenient date. We will summit the date given formerly and invitation letter revised. I am really sorry for make you trouble because of my lack of studying.
furthermore, the situation of the A is not of stock, therefore it was understood that goods are not enough to provide on August 24 as I contacted at first. I am really sorry.
I want you to teach a convenient schedule because I want to readjust a schedule for from September 11 to 15th.
I'll correct your schedule of the Invitation letter and will submit you. This time I bother you by my lack of study and am really sorry.
Therefore we would like to arrange the date during 11th - 15th September.
Could you please advise us your preferable date.
We are going to revise the date in the invitation letter as well and send it to you.
I apologize for your inconvenience my lack of studies caused you.