nodemcuv2.build.flash_freq=40
<-------------------- adding these 4 lines -------------------->
nodemcuv2.menu.UploadTool.esptool=Serial
nodemcuv2.menu.UploadTool.esptool.upload.tool=esptool
nodemcuv2.menu.UploadTool.espota=OTA
nodemcuv2.menu.UploadTool.espota.upload.tool=espota
nodemcuv2.menu.CpuFrequency.80=80 MHz
This created a new "Upload Using:" menu button for the NodeMCU. With the rest of the settings
OTA now seems to work flawlessly using the staging release both initially via "serial / COMx" and then subsequently via "OTA / Port:".
Hope that helps you too. Thanks,
Bernd