Migrated Sonoff Dongle-P to E, some devices not connecting

Hi,
I have just migrated from a Dongle P to Dongle E. (v2) with my HAOS ZHA.

The dongle appears to have migrated OK, but 2 of the devices are not being seen:

SNZB-05P (Water Leak) and SNZB-02P (Temp and Humidy).

(I have two other devices that appear to be working fine - a TRVZB and SNZB-06P (Human Presence)

I have read the top part of this thread:

Options are to 1) upgrade the Dongle E’s FW, and 2) remove batteries, then re-pair the devices.

Before I do that, is there anything else I can try, these will be going into rental premises, and to be able to remotely resolve any devices going offline would be good, I note within HA the Device info reports:

SNZB-02P
Device info/Zigbee info: last seen: xxxxx
The xxxx time is changing at intervals with the last time within the last 10 minutes, so is it being seen ?, yet the Temp and Humidity history flatlined on the last measurement, after I migrated the dongles.

SNZB-05P
Device info/Zigbee info: last seen: xxxx
The xxxx time has not changed since I migrated dongles.

If it is advised to upgrade dongle FW to the newer ‘Ember’ FW (currently 6.10.3.0 build 297 - which I understand is EZSP FW), which FW should I be using, considering I am using ZHA:

From darkxst:

or
From itead

I note NCP or Router FWs available, I need the NCP ? and what does the NCP stand for ?

And I use a flashing utility such as this:

or

Any thoughts appreciated.

The relevant parts of this firmware readme:

Different firmware variants

Three network protocol application firmware variants are available:

  • EmberZNet NCP = Zigbee NCP (Network Co-Processor) is used as a dedicated Zigbee Coordinator for Zigbee-only environments*

Pre-Compiled Firmware

Firmware builds can be found in the firmware_builds folder.

ncp-uart-hw- EmberZnet pure Zigbee

I see this web based flasher:

Should allow me to upgrade my FW easily with this current version:

ncp-uart-hw-v7.4.5.0-zbdonglee-115200.gbl