So even switching power sources isn’t recommended.
Spider Chart issue has been reported under this thread (being worked on) –
Ranking Chart Broken - Support - Xert Community Forum (xertonline.com)
Keep in mind TP isn’t the same thing as FTP and while they are close for many cyclists the tests to determine them are different and so are the results.
I don’t think people should try to equate them or more so treat either as a discrete number. 
They are both mathematical constructs and estimates. I consider them as -ish figures. If I get a small bump one way or the other it means my signature is valid (close enough).
Granted TP/FTP values are used for workout goals but Xert’s approach isn’t based on FTP block intervals and that makes a difference. As does their hybrid polarized approach versus SS. As does their strain approach versus TiZ.
So don’t worry about the numbers matching. 
A difference from Refresh/Recalculate is normal too. Once your starting signature gets dialed in move forward from there.
Unlike other systems that rely on periodic FTP tests Xert constantly recalculates your fitness signature with every activity and every passing day. The numbers are meant to fluctuate as you reach new fitness levels or decay occurs over time.
In your case the jumps were generated from outdoor rides consisting of shorter intense efforts as @Jomavami points out. Compare that to what happens during a workout designed to generate a BT (search the workout library for “breakthrough”). They are very different than a traditional 20 min test.
Also review the BT best practices article (“the Xert Way”) linked below.
As @xertedbrain notes your star status corresponds to current training load which in turn can determine which workout range is best for you at this time. For example, if you start a progression on Xert at 2 stars then recommended workouts will be in 2 to 2-1/2 diamond range. That is why you couldn’t finish Cheung CX Ronnestad (4-1/2 diamonds) at 100%. The others were 3 diamonds which should have been tough but doable. 95% is pretty darn close in my book. 
All were challenging high intensity workouts best approached when feeling fresh.
If you aren’t preparing for a specific event consider GC Specialist instead of TT as a good starting point. Athlete types (focus duration recommendations) fall into quadrants as shown in this chart –
Athlete type progression - General - Xert Community Forum (xertonline.com)
Reference:
Training Status and Form – Xert (baronbiosys.com)
Breaking Through the Xert Way! – Xert (baronbiosys.com)
Fitness Improvement and Day-to-day Variation – Xert (baronbiosys.com)
Cheung’s Ronnestad: Fitness – Power versus Repeatability – Xert (baronbiosys.com)
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Appreciate detailed explanation and I have 2 scheduled events so far, gravel grinder in Oct and GFNY 100mile race next May in addition to weekly group rides. I wasn’t sure I could use Xert so I set up ATP plan in TP using traditional plans. I subscribed for a year with Xert and I do want to try more Xert workouts. What would be a good way to know which Xert workout I can substitute for traditional workout? Should I for example search for TT workouts to substitute threshold intervals? Set an event date and just use recommended workout of that day? Is there a podcast or blog about mixing and matching Xert with traditional workouts/plans?