Where are the deceased during Obon?

If something like a soul is expected, let's put that idea aside for now.
People's lives and deaths are due to the work of Buddhism.
Life and death are at the same time.
It doesn't mean life or the idea of a soul, and it always has the function of being born at the same time as death.
In other words, your father is always everything you see and feel. The okuribi, the smell of smoke, the altar with his hands together, the wind, and the incense sticks are all father's. Flowers blooming by the roadside, the voice of cicadas, and the work of Buddhism are the same functions as father himself. Your father can always be felt in your activities themselves.
The feeling that you care about your father and every move and throw that expresses it is an expression of your vows for the future of your life.
Cherish people and things. Such a pledge to live for others will make Dad happy.

The way of thinking about Obon differs depending on the denomination
In the Jodo Shinshu
Ancestors who attained Buddhism
I haven't stayed in the Pure Land the whole time
To lead people with relationships
I think of it as the Buddha who is by my side.
Can you come back on the 13th
It's not the Buddha who will return on the 16th, is it?

That's why
There is no problem at all even if you pray early.
My father is already
They are standing by your side.

The fact that the deceased returns during Obon is a Japanese cultural event.
However, in terms of Buddhism, we think about reincarnation.
For example, if you have had a previous life, and your descendants in your previous life are Japanese, they may be burning a fire for you somewhere.
That said, your soul won't escape your current body and fly to your family from a previous life.
However, if you are reborn in the Pure Land of Paradise, etc., it seems that you will gain supernatural power and gain the ability to go to another world in a short time like before breakfast, so in that case it may be possible to visit a family member from a previous life.
What is important during Obon is to give alms and memorial services (hospitality) to the Buddhist cult or others, accumulate merits (sow the seeds of good power in the field of the heart), transfer those merits to ancestors, etc., and pray for the happiness of ancestors who have been reborn somewhere and are living a new life.
Also, if you accumulate merits, you can acquire personalities and abilities that make it easy for yourself to be happy.
In other words, doing good deeds for yourself and others is important in Buddhism.
There is also a way of thinking called ideology, and there is also a way of thinking that our minds are connected by deep psychology.
If you sow the seeds of merit in your heart, merit may reach your father's heart as well.
Let's hope your father is happy as he is living a new life.

Since this is your first Obon festival, you're probably confused a lot.
I think the best thing is to ask the opinion of the chief priest who actually prays.

I think the way Shinshu greets Obon is slightly different from other sects.
First, cucumbers or eggplants are not garnished, there are no welcome fires or okuribi, and there is no clean salt. Since it's a milestone Buddhist ceremony called First Bon, it doesn't matter if it's the same as a normal memorial service.

There is a saying that people who died in the Shinshu sect go to the Pure Land due to the work of Amitabha. But I'm not going to keep going. I think there are times when we put our hands together in memory of those who have passed away. That was the encouragement from the deceased and from Amitabha. If so, it's not like they'll come back especially since it's Obon, or that they'll go home when it's over. That's because it can also be said that they came back when their hands were put together. In other words, if you have a day of thanksgiving, then every day is a happy day. I think that's where they don't make special decorations for Obon.

Following the story of Morensha, which is also the etymology of Obon, I think that is the way to greet Obon like Shinshu by joining hands and rejoicing at the opportunity to receive Buddhism together with the deceased. So, I think it's preferable to visit graves during the Obon period, but if you have proper feelings, I think it's fine around that time.

For the time being, I am guiding the followers of Jibou like this. However, I think the chief priest may also have thoughts about praying, so again, I think it would be better to consult with that temple once.

Gassho