日頃から御愛顧を賜り、厚く御礼申し上げます。
通常1ヶ月前あたりから御予約でうまり始めますため、御早目の御問合せ・御依頼を御勧め申し上げます。
Thank you very much for your business always.
You are highly recommended to inquire / book my services with sufficient time frame in advance, as bookings begin to fill approximately a month ahead.