Originally Posted by
Potemy
Just upgrade everything, if you have several available, then decide what's most important to upgrade first, maybe your field or medical facilities if you want to avoid injuries, training to improve your players' progress and to get green packs. The lights and scoreboard/video wall are least important.
For medical, training and youth, do not build it while they are generating your packs/players, upgrade it on the day you get the products from them, because they will not generate anything while you are building, and then the timer will restart from zero when building is completed, especially sucks for youths.