It seems they fixed up the Daily battles.

The rewards have been scaled slightly. I am lvl 40 and got 9 blueprints from the blueprint mission. In addition it seems the mission drops a extra random 3* tanks (tanks of higher rarity have not been confirmed yet). thats another 3 blueprints.
The exp also displays properly, and I got around 1420 exp, which is decent for that oil amount.

Being one to write criticizms I think its only just to say I like the fact the devps. have fixed the issue with the daily Invasion missions and stepped up the rewards a bit. Credits where credit due, Good Job devps, keep it up, improving the game step by step