The play count and warmup timer can be very difficult to grasp for new players, so I am going to do my best to explain how to use it to your advantage.
Each week, Topps will post in the news feed about the settings for the week. These settings will include the number of plays you get, the warmup time, and the reload time. All three are very important to gameplay.
Number of Plays
This represents the number of lineup switches you can make before having to wait to reload. Its the number at the top of the play screen. If you have 18 plays, you have a lot more flexibility to switch out your cards like mad, but it all depends on how long it takes them to reload, which is another factor. If the reload timer is too long, and you use up all your plays, you will be stuck with your lineup as is. Once the play count hits zero, you are done until more plays generate.
This is how long it takes for a card to eventually become active in your lineup and start scoring points. The longer the warmup time, the further ahead you will have to plan. If the timer is 10 seconds, you barely need to wait at all, and can sometimes switch in players as the plays are happening to get those points.
Example: you are watching the game as a player hits a home run. With a short warmup timer, you can switch in all his cards before the game updates and get all those points.
If the warmup timer is 60-90 seconds, you almost have to switch people in during the prior inning to avoid missing out on the points that card will score. This is especially important for pitchers.
It also means it will take that long to get them out of the lineup if they are a pitcher getting rocked. So, keep that in mind as you are putting people in.
This is the time it will take for each play to regenerate. The longer the timeframe, the more important it is to manage your switches. Short reload time lets you go quickly through your switches and not be penalized if they need to be taken out. You will have the plays to do so.
I like to have enough plays in the bank to switch out cards if an emergency comes up, and the reload timer plays a big factor in that. It will also play a factor if you have a small number of plays to use and the pitcher has a quick inning. A longer reload timer will prevent you from switching to the new guy in between.
This is one of the toughest elements for new people to grasp, and its even harder to explain in text. Please let me know if you have questions.