Excactly, you get the point this 60-70 battles you can play only at the first day after you bought a new spellbook (or when you don't play long enough that your account reach 100% ECT)
I posted already myselfe about this:
and in german:
https://hive.blog/deutsch/@udow/splinterlands-versteht-das-splinterlands-team-ihre-eigenen-formel