I do have somewhat of a weird question, but please bear with me

I've read on the forum that some people received their bio letter only 1 or 2 days after receiving their case numbers. Do you know if there is any chance that HO could have sent my bio letter after issuing the case number, but before receiving our complete application? I assumed they wouldn't, but in case they did, the letter could have been lost as I wasn't living at this address yet. If that could be the case, is there anyway to ask for a new letter?
Many thanks!