I allowed 75 minutes on my last intl - domestic connection, however, the intercontinental flight I took circled above the airport waiting for ATC causing about 15 minute delay, and the transfer security took me nearly half an hour to pass! As a result when I passed the security I had only 28 minutes from the departure time of the domestic flight, and I grabbed a phone card immediately in the R-kioski near gate 50, torn the package and inserted it into my phone, ran to immigration and the gate. (I had to buy and activate the phone card before boarding the domestic flight because the phone card must be activated in Finland before using in Sweden!) At that moment the domestic flight was already boarding and it was 22 minutes before departure time. The MCT there was only 40 minutes and it was definitely not enough to clear the transfer security of an A350 load of passengers!
My past transfer experience at HEL was a breeze, but now it is as crap as SVO.