Hei AnetS

I wanted to know myself about Haparanda - Tornio rail situation. 
Getting reservations in Finland is a pain. Stations are not staffed, even in major cities. The eurorail reservation would be mailed to you on paper. Useless. The new App of VR, the Finnish railway, sells full tickets with reservations only. 
Unless your staffed station in Germany, Sweden or where ever sells you a reservation for Finland, 
the only way is by a phone call to Finnish railways. You can order your reservation in English and pay by Credit Card. Phones are answered fairly quickly. 
On 2022-07-25 I travelled Helsinki to Kemi by sleeping car, met two Interrail travellers who were not aware of the time difference, had thus missed the night train in Tornio Itäinen (East). 
I cycled the ~40 km to Torneå älv, crossed that river, walked too and fro over the frontier in the twin cities Haparanda/Tornio. 
The track on the East side of the river is being renewed, I hope passenger trains will run again in 2023 as they did in 1972. 

For just a seat passholders do not need a RES per se (as I was told on a shorter return last may out of HElsinki). And its indeed as above explains: as all local tickets come with a RES-even more if you change trains-and seats as such are not marked, this is a hassle for longer trips-and certainly overnite-at any stop someone may come and claim your seat. VR does have a very few own counters left-with very limited hours, and also the R-kioskki (just like 7-11 in DK or Pressbyran in SE) should be able to sell tickets, but the usual teenagers working there will never ever have done that as seat-only RES.

I have set out this Q several times, but as far as someone answered it was always ´best is to call VR´. 

Some people suggest to check the seating plan-but again: it is very well possible that what looks like now a free seat will be assigned to someone just buying a ticket from the next stop onward.

And yes-in FI it is 1 hour later as in SE-your fone will adjust-after 10-15 mins, but be aware when time is tight.

Don’t trust the time on your phone in the frontier region. 
It keeps changing depending on transmitter mast. Look at your watch or verify the time zone on the mobile. 
Photo: Haparanda station, Swedish time  

Thanks for all the answers, I called VR and for approximately 2,5 EUR phonecall I have got the reservation, so everything worked well. So hopefully the trip ends up well and we will manage to get on trains on time :D

After our trip, I will write some useful hacks :)