There is now an increased risk of eruption in Tungafellsjökull volcano (this is my opinion only). This volcano is different than Bárðarbunga volcano and is not connected to it on crustal levels (46 km top layer of the Earth crust in this area).
There has never been any historical eruption in Tungnafellsjökull volcano far as I know. So I have no data to work with in terms of analysing historical behaviour of this volcano. There is a stress factor at work here from Bárðarbunga volcano, this means that all the activity and drop of the Bárðarbunga volcano is changing the stress in nearby crust, this is the idea for the moment about how activity in Tungnafellsjökull volcano started. There is an increased risk of magma rising from depth into Tungnafellsjökull volcano from all of this. I don’t know why that appears to be the case (based on the data that I got), since magma coming into Tungnafellsjökull volcano is from its own deep root system that is connected to Tungnafellsjökull volcano. Even if magma is entering Tungnafellsjökull volcano it does not mean an eruption is imminent. The risk of an eruption in Tungnafellsjökull volcano is increasing at the moment, it might get lowered again soon, but this is the current status. Tungnafellsjökull volcano continues to have Green status on Icelandic Met Office website.
If anything more happens in Tungnafellsjökull volcano I am going update this article or post a new one.