Certified GKH Gardening Expert
Pineapple fruits take about 6 months to mature, so you should wait at least that long. It looks like this one might have some more growing to do. You can read more about pineapple harvesting here: https://www.gardeningknowhow.com/edible/fruits/pineapples/picking-pineapple-fruits.htm
As far as a bigger pot, you should keep the plant right where it is for now. Transplanting is always hard on plants, and you don't want to cause it any undue stress when it should be focusing all its attention on that fruit.