My Express+ HD with Composite (https://www.roku.com/products/roku-express-plus-2018 Model 3910RW) started behaving in exactly the same way about a week ago - same behaviours:
- the Logo/clock only screen
- multiple calls to update, some actually presenting the error/try again screen, some seeming to succeed
- Sometimes it would finally make it to the menu screen, but every channel we tried to launch from our favorites would say it couldn't download and run
- Sometimes it would finally make it to the menu screen, we'd start watching something only to have the system auto-self-reboot 15 minutes into the show.
Eventually, we found that either exercising great patience would allow the system to get to a menu screen (it would auto-reboot) and allow us to watch entire shows without incident, OR when it either at least made it to, but then hung on the logo/clock only screen, pulling the plug and re-booting it would eventually get it working again.
So every night we've been powering the Roku up earlier and earlier just to cycle through the repeated updates and reboots.
And I've tested my network connectivity when my Roku finally "gets its brain back" and it's good - so that's not the culprit.
I found this other thread (https://community.roku.com/t5/Features-settings-updates/Roku-express-cannot-update-3930x-no-matter-what-I-do/m-p/942037) where someone advised that there was a problem with the recent update, saying:
"The latest update - 12.5.5.4174 - is broken - once installed the 3930x does not work. Thus it is probably good that you cannot upgrade. Perhaps Roku have withdrawn the broken update until they can produce one that works?"
And frankly I was beginning to get the impression that this might be exactly what was happening to your and my device: they are stuck trying to apply an update they have downloaded that just isn't going to work - and they have a built-in safeguard to eventually revert to the older version if they can't, but you are forced to cycle through trying the update and multiple reboots before the software reverts to a "last well known good" version.
That said, I found this other thread (https://community.roku.com/t5/Features-settings-updates/Roku-3930X-is-stuck-on-bouncing-logo-screen/td-p/941737) where Roku "recommend proceeding to factory resetting your Roku device" and the user reported that having solved the issue.
I can't say I recommend it, but maybe it "clears the device down" to a point where the update can "finally take".
I'm too chicken to try a factory reset because I don't want to entirely "brick" my device because they don't make the 3910RW anymore and I absolutely need the composite out for my audio soundbar. I wirelessly send the HDMI video to a speakerless ceiling mounted projector via a DVDO Air3c setup behind us, but have the wall that gets projected onto, soundbar and the Roku in front of us.
I hope they sort this out soon - it's REALLY annoying!