I also have the same case, I have received my wife’s H4 Change Of Status Form I539 Receipt which was generated on April 17th, but i haven’t heard anything so far about my case. My employer’s attorney filed my H1B application and my wife’s H4 application together with USCIS.
As per some people, if the packet is opened my H1B petition would be selected, how sure you are? And has this been the case earlier and documented as part of any email or article published by anybody else earlier? It may also happen that they open the packet and keep H4 for processing further and keep my H1B application Form I129 for the draw and issue the receipt for my H4 as they received it, but once they complete the draw and if my H1B application does not make into lottery selection, then they take decision on wife's H4 and deny the change of status also. This is again just my guess, not sure how USCIS manages the application packages and do the lottery without opening the packet or after opening the packet.
Please advice. If anybody had the same case and received the H1B application receipt also, please let us know as well.