If your client is interested in Accelerated Mobile Pages, get it in writing and include a fee for undoing AMP if they don't like it. If you don't update Google's AMP project cache directly with a special URL for each and every blog post and page URL you AMP, Google holds onto the AMP page in its SERPS and CDN for eternity! Even doing the reminded and manual URL update, this stuff can still be around for a month. Ugh.