How long for a paper Partership return SA800 to show as 'received' online

Hi, I posted 3 partnership returns (SA800) to HMRC in same envelope on 24th May. By the 6th June two were showing online as received on 29th May, but one still does not show as received. Should I send in another copy of the return for the one that seems to have been missed out? The only difference with the one not showing is the partnership ended during last tax year (5/4/24), though don't see why that should make any difference.

Hi

All paper post is digitally scanned into our electronic post service, for manual processing.  
It would appear from what you mention, that two of the tax returns were processed and appear online,  If all three were in the same envelope, we should have the remaining return on hand.  
You would need to progress chase this via our self assesment helpline on 0300 200 3310 or through our webchat facility at Contact HMRC.

Thank you