I'm replying to my own post in case someone may find the information useful.
1. Lectric eBikes support did not respond to my request for info on the XPremium chain, so my one and only experience with their support has been negative.
2. I purchased the Shimano HG71 which is 116 links long.
3. I removed the original XPremium chain to compare against the Shimano. It is a KMC chain that is 126 links long. It uses a KMC CL573 quick link which is not reusable. To be safe, I replaced it with a CL573R which is reusable. The KMC chain does not look like photos of KMC's eBike rated chain I have seen so I don't know exactly what kind of chain it is.
4. I purchased another Shimano HG71 chain and spliced together a 126 link long chain. I carry the spare chain with me on my XPremium along with a spare tube and some tools.