What will happen if I upgrade the laboratory while upgrading a spell or unit?
I know from Personal experiance that the Spell-Upgrade will Pause while the Building is upgraded and will resume where it was once the Bulding-upgrade is finished.
It will still be upgrading, but with a caveat.
I had the same question myself and due to the timing of some of my upgrades, I was presented with an opportunity to easily test this. Here's the scenario for my test:
- Freshly upgraded to town hall 8
- An idle laboratory
- A huge pile of elixir
Here are the steps I took for my test:
- Started upgrading my balloons to level 4 (takes 3 days).
- Waited 15 minutes or so.
- Started upgrading my laboratory to level 6 (takes 4 days).
- Periodically checked my barracks for my balloon's level over the next 4 days. Was still level 3 for the entire duration.
- After 4 complete days, received two notifications that my laboratory had finished upgrading and that my balloons had been upgraded to level 4.
- Entered the game and immediately received an in-game message that my balloons had finished upgrading to level 4.
- Verified in my barracks that my balloons are now level 4.
Conclusion: It seems that the troop upgrade continues in the background. However, if the troop upgrade were to finish in less time than the laboratory takes to be upgraded, it will not be completed until the laboratory itself has also completed upgrading. This also seems to imply that troop upgrades which take more time than the laboratory takes to be upgraded should continue, but I'd need to test that specific scenario in order to be sure (and that probably won't happen for a few months at least, if the opportunity even presents itself).
I wanted to share this information that, you can upgrade both your troops and your laboratory simultaneously in COC. I tried with my two different accounts. In account1 I queued to upgrade barbarian and upgraded research lab the same time and bingo, it worked accordingly. And in account2 upgraded balloons to level 2 (that take 24Hr) and upgraded lab to level 2 same time (takes 12 hrs). When the laboratory was upgraded I found balloons in the queue for less than 12 hrs to complete the upgrade. Cheers.