Can I be living separately from my husband? to remove condition of GC

We've been married for 3years. We lived together for 2.5yr, but because his mom's health issue, we were back and forth of East/West Coast, and it was expensive to stay in hotel so we rented an apt under his name near his mom. and rented an apt under my name in CA. (he didn't get qualified for the APT in CA because of his debt, so we only put my name). Now, he got laid off end of last year,he moved to where his mom is. but, i still have a job in CA. we filed i-751 in November before he moved, but have not gotten any notice for interview ( i did fingerprint). do we need to report his move? he had to file tax in 2 states because he worked temp whenever he went to see his mom. i feel like it seems that we live separately. I have letters from his parents to prove our marriage, and pictures. SHould I report his move? or should we just wait till we get interview and just show up on the interview? he is willing to drive back for it but we'd rather avoid it if possible cuz it's so far drive.