I would like to purchase a MKR1500 which has current firmware in SARA. Does anyone know if this exists and if so where to order? The posts I've found on upgrading the firmware don't have very clear instructions, at least for this old man. I did get the current firmware from Ublox.
After finding the excellent instructions from zbelding for updating the firmware using the passthrough sketch and ExtraPutty, this is no longer needed.