There is a good amount of documentation on EEPROM, but I'm still a little unclear on the effect of page erases.
My question is, do you lose stored data during a page erase?
Here's some of the docs that seem a bit ambiguous to me as it pertains to data integrity:
Unlike "true" EEPROM, flash doesn't suffer from write "wear" with each write to each individual address. Instead, the page suffers wear when it is filled. Each write will add more data to the page until it is full, causing a page erase.
After enough data has been written to fill the first page, the EEPROM emulation will write new data to a second page. The first page must be erased before being written again.