Timber is a natural material so please make sure that all tonewood and timber is kept under control.
Excessive humidity can cause wood to swell and under stress will warp, twist, & bend, keep the temperature & humidity under control.
Keeping the humidity between 40 & 50 % will unsure stability.
After you receive your tonewood please sticker and rack and allow to adjust to your environment.
Musical instrument sets should be stored flat with weight on top unless totally sealed wood takes on and releases moisture which causes expansion and contraction, when wood expands or contracts due to changes in humidity or temperature it can change shape.
If kept in a weighted flat stack with pressure across the entire face of each panel with no overhanding or unsupported edges or ends your wood will remain perfectly flat for as long as you wish to store it.