Mainly inform the customer why the delay may occur, give the customer an expectation, and finally thank the customer for their understanding.
Dear customer,
Thank you for your purchase and prompt payment. China will celebrate China Spring Festival,from 30 Jan. to 5 Feb., both days inclusive. During that time, all the shipping services will be unavailable and may cause the shipping delay for several days.
We will promptly ship your item when the post office re-open on 6 Feb.. If you have any concerns, please contact us through eBay message. We apologize for the inconvenience caused and appreciate your kind understanding.
Wish you and your family have a happy time together as well.
Best regard,
(Your name)