Bus to Takayama during spring festival

We plan to arrive to Takayama from Matsumoto on April 13th.
We already made a reservation for a hotel in Takayama for the 13-14th.
We saw that the bus from Matsumoto to Takayama leaves only 3 times a day, morning, noon and afternoon. Tha last bus leaves Matsumoto at 17:45.
We found no way to make a reservation for that bus, and are worried that we will have no seats on this bus since it is the night before the festival starts, and many people will try to take that bus.
Is there a way to guarantee a transportation from Matsumoto to Takayama?
Thank you!

From matsumoto to takayama by alpico kotsu bus cost 3500 yen,89 km,165 minutes
By nohi bus 3400 yen,you can also travel from shin shimashima bus terminal

Thanks for the topic. Right now my itinerary would lead me to Takayama roughly 1 week after the spring festival.
But I could change my itinerary and take the same bus from Matsumoto to Takayama.
There seem to be 6 connections/day in total.

https://www.nouhibus.co.jp/highwaybus/matsumoto_en/#timetable

Reservations are probably not possible since it is a regular bus connection.

There are no reservations and you cannot buy in advance. It is frustrating, especially as they reduced the number of services due to lower passenger numbers.
There are only THREE connections a day, not six. Three terminate at Shinhotaka Ropeway.
The company does potentially have the ability to add additional buses if demand is high, but I have seen no indication that they have this planed for the spring festival.

In case it helps.
I have been to Takayama some 5 yrs ago during a typhoon and the train connection Takayama- Nagoya got closed. There were quite a lot of passengers who this decided to take the bus and Nohi was able to add more busses. And this was relatively unplanned. While the matsuri in Takayama is an event they can plan for. So Ifd kind of EXPECT that they put additional busses. Not additional departure times though.
Anyway, be there early.

Oh, I missed that one. Thanks for the correction. Not all of the buses go all the way to Takayama.
But it's confusing since the website says that only 2 terminate in Shinhotake?

Do people usually stay 14. and 15. in Takayama or is one of the two days enough to experience the festival?

Further to @LikeBike's comment (I chose not to cover this as it is partly speculation on my part), at Takayama the bus depot is very close to the bus terminal. If they have a lot of extra demand they can quickly put on an extra service if they have driver/capacity. I am not sure where the depot is for Matsumoto. (And, yes, I also almost got caught in Takayama due to typhoon around five years ago, but left a day early and managed to get home.)
I have experienced the company putting on an extra bus at short notice in Nagano where Nohi bus (they run the buses in the area) put on an extra service for me and my group, but that was unusual circumstances.