As we know, there's no Russian pipeline gas sales. Estonia and Finland were building floating LNG terminals, one in each country but also collaborating. It is expensive. A floating LNG terminal is basically a rented LNG tanker that has gasification equipment onboard. It's next to a pier with a natural gas pipe. In the end it was placed in Finland. The Estonian terminal construction was halted. Tanker is rented from USA. LNG is brought to the floating terminal, gasified, put to pipe network. There's this pipe between Finland and Estonia too.
Finland actually buys and ships the LNG for the terminal from ... Russia! This is because of existing contracts that can't be breached because there's no EU wide sanction for LNG buying from Russia.
Finland does not heat any houses with gas (There was a little bit in district heating). Also Finland has energy abundance since Olkiluoto 3 coming online and massive amounts of wind built in the last years. Also hydro and great grid connections to Sweden, Norway and Estonia. I think there has been very little use for the LNG in Finland.
Estonia is still grid connected to Finland and grid and gas connected to Latvia. Closest LNG terminal in the pipeline network is in Klaipeda, Lithuania. There's also the aborted LNG terminal in Estonia's Paldiski that's relatively far along.
So the real target of this attack could be Estonia and Baltic states in general.