Please see the following comments.
1. Is it possible to program or erase to another sector during the Suspend command?
As mentioned in “8.6.5 Program or Erase Suspend (PES 75h)” in the datasheet,
a. An Erase can be suspended to allow a program operation or a read operation.
b. A program operation may be suspended to allow a read operation.
2. When resumed with Resume command, What is the status of the sector where the program or erase was suspended?
When program or erase resume command is issued, the flash will continue with the suspended operations.
User can check WIP bit in status register to check the completions status of the embedded algorithm (program or erase).
3. What is the status when the power is turned off while there is a sector where programming or erasing is suspended? Is it possible to access the sector?
When there is a sudden power down after program/erase suspend, user has to program/erase the memory locations again in next power cycle.
4. Are there any other points to be aware of besides Suspend Latency (tSL)?
User has to make sure the timing parameters tSL and tRNS are met during suspend and resume operations.