My spouse has H1-B until 06/12/2019. We applied for COS to H4 with effective date starting 06/13/19. When we received the I-797 approval dates for H4, it had start date of 05/20/19 (USCIS mistakenly must have followed my H1b extension start date, ignoring our requested start date of 06/13/2019as listed on her I-539 COS application). So now technically from 05/20/19 thru 06/12/2019 she will be on both H1B and H4. Can she continue working from 05/20/19 thru 06/12/19 based on existing H-1B or should we contact USCIS customer care to correct the dates and new I-797 approval notice reflecting original request based on I-539?