Multiuse License

I have produced a series of social campaign videos for a client to use as a promotion for their competition in which their end customer buys their products and goes in the draw to win something.

There is roughly about 10 videos in the series.
Do I need to purchase a standard license for each individual webisode or can I just purchase one standard license for the whole 10 videos?

The end series will be only on Facebook, Youtube, Instagram etc (However, my client has over 2 million followers on Facebook) which license is needed?

Many thanks!