Good Morning,
Thanks for using Ask a Master Gardener with your houseplant question.

Adromischus cristatus, also known as the Crinkle Leaf Plant or the Key Lime Pie is a plant in the Crassulacecae family. That is the family of the Jade plant.

The photo of the plant that you sent is not a normal form as the plant usually forms a rosette. Your plant could be experiencing stretching due to not intense enough light, causing the nodes between the leaves to lengthen, or could be potentially ready to set a flower spike. The flowering of the plant also can cause the nodes to stretch. Cool conditions will also slow down growth of this plant. Normal leaf size is 1" wide by 2" long.

To answer your question about repotting, you will get more vigorous growth with repotting as the plant will have more space for root development. To see if the plant is currently pot bound, carefully turn the pot upside down and slide the soil ball out of the pot. If the roots are a tight mass, then the plant will benefit from a larger pot. Do not use a pot larger than a 6" since it is in a 4" now. You only want a new pot 1-2" larger than the current pot. Carefully loosen the roots that are tightly held in the soil ball and add fresh, free-draining potting soil to make up the difference in pot size.

Once you have competed the repotting, place the plant in a bright light site similar to the photo you sent, then over the next month, move it to brighter light. If you place it in full sun immediately after repotting, you might get leaf scorch or sunburn.

Normal growth times for this plant are Spring and Fall with no new growth happening in the Winter (low light) and Summer (most succulents try to maintain water loss at this time due to high heat). I would use some houseplant fertilizer at half the package recommended rate when Spring get here (maybe about May).

Just to let you know, when you buy a new houseplant, it is not uncommon for leaves to drop off. The leaves were produced under a high light condition in a greenhouse and the lower light conditions of a home make those leaves inefficient since the light intensity is lower. Therefore, the greenhouse leaves will drop off and be replaced by a lower light tolerant leaf.

Here is a fact sheet about these plants:

http://mpb.ou.edu/plants/week127.shtml

I trust this will give you direction to be successful with your plant. Thanks for the question.

Thank you for all the helpful information.  Being that it’s winter, is it okay to repot now?  I thought reporting should be done in the spring but maybe not the case for all plants?  

You are correct that Late Winter/ Early Spring is the suggested time for repotting, but I tend to do it whenever I have the time and since they are inside in an artificial summer, I don't give it much thought.
The thought is in the Spring, the plants will actively produce new roots to establish the plant before the following winter. I believe that you would be fine to begin the process now as Winter surely will come to an end soon.
Dave