It does seem an unlikely jump, but anything is possible when you finally get to ride outdoors.
What does the BT report look like?
View the activity and click on the BT badge icon then post that report here.
Are the majority of your indoor workouts using the EBC app paired to your bike’s power meter so Powermatch is active?
I am gone until tomorrow but someone else will probably chime in.
I barely use the EBC app as I am new to Xert, but I am starting to use it more now. I’ve only been using the wahoos build power meter for zwift and this is the first time that I used a power meter while riding outdoors (Vector 3).