Adventurer's League Handbook said:What happens when new player rules options
are released?
New player rules for characters are tied to storyline
seasons. When you create a character, you choose
the story origin for the character, which defines what
rules you can use for the duration of the character’s
career. If you want to use a new rules option from a
book outside your character’s allowed rules, you need
to create a character with a story origin that allows that
rules option.
Yes. This, a thousand times. Electronic tools are nice, but not if using them means I have to drink from the firehose.I love options. The only issue I ever had with these books is with 4e DnD Insider. Having _all_ the options in an electronic format slowed down character creation to a crawl, made it more likely to have unbalanced options, encouraged min/maxing a bit too much for my tastes, and put me in a position of saying "no" more than I like as a DM. With physical books you could have exactly the same issues, but in my experience we did not have it to that extreme.
So while I love options, I'm hoping that future electronic tools make it easier for me to filter out the options I don't like, and I'd be happier with fewer, higher quality options. I like to say yes to my players, not no.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.