add release note

Author: wpbonelli

doc/ReleaseNotes/develop.toml

@@ -47,4 +47,11 @@ description = "The adaptive time stepping algorithm (ATS) was not working correc
 [[items]]
 section = "fixes"
 subsection = "parallel"
-description = "Mover (MVR) Package connections across two or more models running in parallel were previously supported for flow but not for solute or energy transport.  GWT-GWT or GWE-GWE exchanges that also include MVT or MVE connections, respectively, is now supported for simulations run in parallel mode."
+description = "Mover (MVR) Package connections across two or more models running in parallel were previously supported for flow but not for solute or energy transport.  GWT-GWT or GWE-GWE exchanges that also include MVT or MVE connections, respectively, is now supported for simulations run in parallel mode."
+
+# TODO this item seems to lack context now, but will read naturally
+# when it follows an item for PRT ATS support, which is coming soon.
+[[items]]
+section = "features"
+subsection = "model"
+description = "Introduce a new PRT OC option SCRATCH\\_BUFFER enabling the scratch file memory buffer approach."