The USCIS has published a Final guidance on when to file an Amendment or New H1-B Petition After the matter of Simeio Solutions, LLC.

The Memorandum brings out some good news and Increased the harbor period to file the Amendment as below:

• If you moved to a new place of employment after the matter of Simeio Solutions, LLC (April 9, 2015) but before August 19, 2015, you must file the H1-B amendment petition. USCIS has no where specified that it is mandatory to file Amendment if you have moved before April 9, 2015. 
• It is clearly mentioned Even if the petitioner does not file the amended or new petition by this deadline, USCIS will generally not pursue new revocations or denials based upon failure to file an amended or new petition. This is one great news.
• The deadline has increased to January 16, 2016, for those must file an H1-B Amendment.
• Although the H1-B Amendment is denied but the Original Petition is still valid, the H1-B employee may return to the place of employment covered by the original petition(In this case, it's your actual employer, not the clients) as long as the H-1B employee is able to maintain valid non-immigrant status at the original place of employment. This has brought down the risk of losing the employment. 
• It is not required to file an H1-B Petition for a short term placement upto 60 days without obtaining a New LCA provided there are no material changes in the terms and conditions of the H-1B worker’s employment.
• If the change of employment happens On or After August 19, 2015, the petitioner must file an Amended or New Petition before an H-1B employee starts working at a new place of employment not covered by an existing, approved H-1B petition.
• The employees intended to travel outside US after they moving to a new place of employment must file for Amendment, which is an existing policy.