History looks a bit sparse prior to mid-April to adequately establish a starting signature.
Were the two bronze BTs from long outdoor rides?
How many days/hours per week do you plan to ride moving forward?
A BT on a Z2 level effort shouldn’t be possible. I’d flag the activity (exclude from sig calc) and consider performing a BT workout in slope mode to confirm your current signature. You can do that in as little as 30 minutes. Much easier than a traditional 20-minute test.
Example: Xert - Workout Details (xertonline.com)
Ride entire workout in Slope mode (gears/cadence to meet or exceed targets) and make sure the last interval continues until complete failure. This type of workout could be ridden outdoors if necessary.
Lots of newbie tips posted here – Beginner questions
Academy series videos are the quickest way to get up to speed – Discover + Improve + Perform
FAQs here – Support Home – Xert
Welcome aboard. 