canceling upgrades during pause

[icomeinpieces]

is it normal for an upgrade that is started and canceled during the same pause moment to only give half back?
i paused, upgraded a few tents, canceled the upgrades as i wanted to try building something else with the wood and realized i only got half the wood back.
the upgraded hadn't been given a chance to start ticking off yet.
a new building in this state is 100% refund, so i would have expected a canceled upstarted upgrade to be the same.

is this a bug or expected function?