According to Cypress' internal database, the S29GL256P11FFIV1 is still active and currently orderable through authorized distribution.
The S29GL256P11FFIV1 is scheduled to the in production through 2022.
In regards to the S29GL512Pxx, this family series is discontinued and is now obsolete, to also include the S29GL512P11FFIV2x.
The Last-Time Buy date was April, 2017, and the Last-Ship Date was October, 2017. Please launch the "Product Termination Notice"
(PTN) #162501A for specific details in regards to this obsolescence.
PTN_162501A.xls 97.5 K
Many thanks for the detailed answer.