Yup. Same thing here.
Web UI shows Pi-Hole v 3.0 Web interface 3.0 FTL Version and "update available."
Howwever, running pihole -up reveals NO update available.
Web interface says " Lost ... connection ... to ... API"
Status (upper left corner of web UI) shows no CPU temperature and FTL is offline (I never disabled it)
Can you run pihole -d and get us the debug token so we can take a look at the local repositories?
Hi Dan. token: wj1zg9h27o.
TU! :<)
Okay, the local repositories show that they are up to day, however that debug log is the old version. It appears that the update did not copy over the contents of the local repositories over to their proper locations in the rest of the Pi-hole. Can you run a pihole -r and see if we can get the files moved to the right locations?
Rpair or reconfigure? Repair, I guess?
Yes, lets try the repair for now.
Bingo! U da man, Dan! 
I really appreciate your help.
... Was just telling my wife ... How is it I can get real0tiemn help from one of the developers of software I consider to be very valuable. I sent u guyz only about $40 and you are unlikely to associate that contribution with me.
Now, if I have problems with Act!, Windoze, QuickBooks, etc, the support is nil or really expensive.
Something wrong with this picture. So ... I'll send you a few more $$.
Glad to help!
Thank you very much for the donation, any bit helps and keeps us going with the ability to develop and support on our various channels.
I had quite the same problem, but running pihole -r stopped with
ERROR - Unable to update package cache. Please try "test_dpkg_lock; apt-get update"
There was one apt repository offline which has no relationship to pihole. The warning seems to stop the repair script. After I remove the apt-source the script runs without problems.
But I had to run reconfigure.
Formatting domains into a HOSTS file...::: No IP Values found! Please run 'pihole -r' and choose reconfigure to restore values
After reconfiguring with the stored values everything works.