Tegra

I note that the app went down again this morning at 06:15

I have just chatted with Sunsynk's helpdesk and they acknowledge having a data/programming problem and request 24 hours patience to fix the issue.

I have just chatted with Sunsynk's helpdesk and they acknowledge having a data/programming problem and request 24 hours patience to fix the issue.

Hi, I'm referring to the Sunsynk Logger (dongle) as depicted in the image on the left.  Not the one with the antennae and RS232 cable.
I can connect to the unit and set its Wi-Fi but it remains 'initializing' with the Cloud.  Never connected. Only the green light remains lit.  

If you go on the remote sunsynk page
Under gateway you will see this. Some documentation I have seen shows a upgrade option there.
It is more for curiosity

Just reset my static IP address to unchecked and et voila I'm back online on both inverters. Thanks. Fixed IP addressing for my network clearly not the way to go. Its now randomly choosing its own IP on my network. This has also fixed the duplicate IP address issue I previously had and could not explain (4x IP addresses for 2x loggers). Have also updated the logger software. Don't see any difference.

Good evening, Yellow_TapeMeasure, I too have an Ubiquiti Unifi AP-AC-LR network in my home (multiple access points and dedicated 2.4GHz and 5GHz outputs).  The network was installed long before the Sunsynk system and is extremely stable with a fibre connection to the www.
The Unifi network also happily runs IDS HYYP for my alarm system (2.4Ghz), multiple CBI Astute devices without any issues, also Google home, my Yamaha hifi, multiple Xiaomi TV devices and Samsung TVs.  The Sunsynk system was installed in September 2022 and ran smoothly on the Unifi 2.4 GHz wifi network until this past Monday.   No devices have ever had connection issues.  Even Sunsynk, until Monday 16 Jan.
The only thing that has changed in the entire solar system is the firmware update from Sunsynk.  The logger for the Master inverter failed to connect, while the logger for the Slave sustained its connection.  On swapping the two loggers (on the advice of Sunsynk) the functional logger from the Slave inverter survived 28 minutes on the Master inverter and then exhibited the same failure mode.  Now both loggers are dead.
Of course, I also tried the trick of trying to connect via a mobile phone hotspot, with the home unifi network switched off.  The logger was able to be set to the android 2.4GHz hotspot but still failed to connect to the internet.  Status 'not connected' and Cloud 'initializing'   The second failed logger now has the same failure and is also not able to connect.  The logger(s) just show a constant green light.
Sunsynk's advice at this time is for me to courier the two failed loggers to them to investigate the failure. The contact person at Sunsynk JNB is [email protected] 
Simply replacing non-functional loggers is not going to solve this problem.  Another two loggers will simply die.  My installer is going to give me a 3rd logger and I fully suspect that it will die as well.  Sunsynk will receive a courier package with 3 dead loggers next week.
I have already advised Dino @ Sunsynk of at least three other people concurrently experiencing the same problem.  I reiterate that this problem will multiply as I fully suspect a firmware update being implicated.
Zero feedback has been received from Sunsynk (UK).