Lightroom CC: Migration details stored in the library for features down the line?

Just wondering if there is any line on whether the features that are missing in the Lightroom CC mean it's worth holding out until later to migrate, or is the information still somewhere in the CC library that can be used if the features are introduced in the future?

For example. I have facial recognition tags on all my images as it's mainly pictures of my family. What I worry about is migrating today, and taking the hit of not having facial recognition as the Lightroom CC workflow adds benefits that outweigh the loss. However, if say in three months time, they include facial recognition in an update, would the files that I migrated now carry the facial recognition data, or would it be lost?

Hence wanting to know if it's best waiting until all the essential features that are included are available in the software before migrating.