Monthly challenge / daily average calculations in the activity app

I noticed that the daily average calculation as part of the monthly challenges in the activity app is somewhat erratic and not always correct and wouldn't allow me to complete the challenge if I listened to the recommendation. Am I the only one with this issue?

Example:

Monthly challenge: burn 20100 calories.

Burnt so far: 19350 at 22.50 of the 28th April.

Difference: 750 to go.

Days left in the month: 2 full days and 1 hour 10min.

Activity app recommendation: Try to burn 250 calories a day for the rest of the months.

That only works if I would have burnt another 250 calories in the last hour of the day even though I already hit my move goal.

Today

Burnt so far: 19425 at 11.30 of the 29th April

Days left in the month: 1 full day and 12.30 hours.

Activity app reco: Try to burn at least 675 calories a day for the rest of the month.

This disregards the 12.5 hours I have still left today?