leenico said:
I read that as "but if that won't happen I'll know enough to wait".
In this case, "sapere" is very close to "potere"
It is more 'I will have the capability' than 'I will have the knowledge'
In these cases, we were taught to translate 'sapere' as 'can' or 'be able to' in English.
I hope very much this explanation make sense to you
