Since it's pretty much impossible to set up a rule for a random schedule, I'm assuming what you want is a way to copy and paste meetings, so that you can copy one meeting, and then go to each month and paste it in the correct day. Or at least enter then more quickly.
You can do this with Calendar 5. Well, mostly. Tapping and holding on an even in month view gives you a copy option. Tap and hold on another date and you can paste. You get the edit window where you can make any changes, then save. However, it only works once. To paste again you have to copy again.
So the workflow would go like this: make a meeting, copy the meeting, go to next month and paste, copy that month's meetings, got to the next month and paste, repeat as needed.
Calendar 5 will sync with the native Calendar app, so it's pretty easy to set up and use.
There are probably calendar apps that will do this even better, but Calendar 5 is what I use.
Another option is to use Siri to enter events. You would say something like "Add an all hands meeting on January 28 at 9am", review Siri's feed back for accuracy, edit if necessary, then confirm. After a little practice you could probably rattle off a few months fairly quickly.
Calendar 5 also has a natural language entry ability, that when combined with dictation, will work much the same.
When you are done you can use search in the calendar to get a list of the events, so that you can double check for any errors. A good idea in this case like this, I'd say.
