According to latest news a large cauldron has formed in Dyngjujökull glacier. The cauldron is about 1 km wide and it is deep (no mention of how deep it is in the news).
Update 1: No eruption has yet started. It is however now expected to start without warning. The cauldron are forming due an rift valley formation in this area.
I will post more information about is when I have more details.
Article updated at 12:40 UTC.
Article updated at 12:42 UTC.