The net effect should be the same--both rules will create a "subscription," internally, that will wake the app to perform the desired action at the specified time. If your rule actions are related, some people prefer to keep them in one rule because that is fewer apps in your list and fewer places to look to modify the automation if needed (but on the other hand, I wouldn't recommend trying to cram everything into as few apps/rules as possible just because you can, something you occasionally see with new users of "full" Rule Machine; I do this only when it makes sense).
So, either way should be good, and with a simple example like this, I'd say it's just a matter of preference.