This stress will be tensile during temperature decrease, or compressive. during temperature increase. If the compressive stress level exceeds the column buckling resistance of. the restrained length, then lateral buckling (or snaking) will occur.
Dry Time. In most cases, you should allow the grout to dry overnight before using that room as total dry time may take up to 24 hours. If you are thinking about sealing your grout after you have installed it, you need to wait even longer than that so that all of the moisture has had time to be released.
Usually directions tell us to grout within 16-24 hours when using sealer as a grout release. I would grout 2-10 hours after applying the sealer to be safe. After grouting, do the final cleanup either the next day or a few day later to allow the grout to cure. You can apply sealer on the tiles and grout after waiting at least 3 days.