Earned Value and Schedule % Complete in activities not in Baseline

Hello,

I have a question regarding Earned Value and Schedule % Complete.

(This happened in a real project, but for sake of simplicity I'm showing a test project.)

In an ongoing project, not so rarely it may be possible to have the necessity of "splitting" an activity into two (let's say, an installation of an equipment which was planned in a single activity, but in execution, it would be done in two parts in separate dates for a reason)

(The project before the split of Activity 1)

(Activity 1 split in Activity 1A and 1B - done by copy/paste activity)

When the copied activity Starts and has a non-zero % complete, the Earned Value from this activity isn't calculated, since Activity 1B doesn't exist originally in the baseline (see the picture below).