Chet, I know someone who recently had a major house fire; she, too, was given a time limit.
The right parties to ask are your agent & adjustor. Tell them being a second home it's hard to remember everything & ask what happens should you later recall more.
For future reference, Chet, this is why you should walk through your home with a video camera to create a visual record of contents, including opening closets & drawers; video everything. Insurers want very specific information about contents; receipts, descriptions, values, etc. right down to the last can of beans in your cupboard, & this burden falls to you. The video record is considered a good alternative to having receipts for absolutely everything & it will help make your job easier in an already stressed time.