Subscription for 1 month ending, will quota change if new subscription?

So what I'm asking is that, will my quota (or limit, which is 100 in the Pro subscription) be cut down to 25 once I subscribe to Plus subscription later? Or will it retain until tomorrow, and that's where the 25 quotas will take effect?

Thanks in advance for all the people who'll respond! (This is because it's my first time purchasing any kinds of subscription too, so I'll be glad if someone can help me through this.)