Is it possible to tell Search Engines that the site will be mothballed for 1 month?

Question

Search Engine Optimization

A crazy request from a client - by all means close his old site indexed in the PS with a stub - for exactly 1 month.
those. in a month this site will work again with all its pages and the same content.
What to do?

Answer 1

Give 503 error site is temporarily unavailable

Answer 2

as an option: put on all pages at the very beginning (before the html tag) a div with the size of the whole screen and absolutely overlapping all content, hide the scroll bar.
and the wolves are full and the sheep are safe =)
although this will probably not affect the positions in the PS issuance for the better, but at least it will not fall out of the index at all