We are on holiday between (month) (date) to (month) (date).
Thank you very much for contacting us and we apologize for any inconvenience caused due to our holiday.
When we are back, we will be getting back to you as soon as we can. Thank you for your understanding.
ご質問ありがとうございます。
* "We are on holiday between (month) (date) to (month) (date)."=「●月●日から●月●日までお休みをいただいております。」
* "Thank you very much for contacting us"＝「ご連絡ありがとうございます」
* "and we apologize for any inconvenience caused due to our holiday."＝「そしてお休みによるご迷惑に対してお詫びいたします。」
* "When we are back, we will be getting back to you as soon as we can."＝「お休み明けに可能な限り早くお返事いたします」
* "Thank you for your understanding."＝「ご理解ありがとうございます。」
ご参考までに。
アメリカ合衆国 
