Finally in
#Vilnius, some 6 min late (it was 13 at some point). +40 min added already in the schedule for track works or something.
Easily 16 hours from central Helsinki. Possible, but perhaps not recommended, at least often.
Elron does have a later direct connection to Riga, letting you have a night+work day's length there, but now it's Riga–Vilnius that has only one train.
From here on to Poland there are three, though the latest one doesn't get you very far into the country.