DDP questions regarding first & last days of trip

[1sttimecruz]

We are going to WDW for the first time this March. We have the DP and I'm trying to make my ADRs now, some are done and some I'm still trying to figure out.
We will arrive on Sunday and I want to check-in at WL early in the day. I'm told that they will let us pre-register and hold our luggage til our room is ready and we can get our tickets and go to the parks. What I'm not clear about though is how the dining plan will work.
Will I be able to start using it early in the day as well (as soon as we get to the parks)?
Also, we check out on Thursday. If I save credits to use at a breakfast TS meal (like Chef Mickey's) will that work- can I still use them on check out day?
Thanks for helping someone who is new to all this!

 

[PrincessTrisha]

When you check in (even if your room is not ready) you will be provide with your "Keys to the World" which will include your dining plan so you can use your credits right away.

And yes, your credits are good until midnight of when you check out so you can certainly save them for a last breakfast.

 

[1sttimecruz]

Thanks so much ~ that info helps a lot!