Is this the rest of Irvine's former music band on page 7?
First panel on the bottom, the musician between Casca and Farnese looks a lot like this guy to me...
[...]
Could an apostle be from this island?
Meh, I'm most likely reading too much into this...
You definitely are reading too much into this. They have the same kind of hat (a type of medieval hunting hat), and... that's about it. Irvine plays a lute (an instrument where you pluck strings), while that nameless elf uses a kind of violin. Putting all of that aside, the likelihood that a human could have become an apostle on Skellig is very, very low. Not to mention that I have a feeling hunting animals isn't viewed kindly there either.
Irvine stated (episode 250) that he's wandered and lost track of time (well my Berserk collection is in French, not sure how they translated it in English...) and with Elfhelm and it's relation with time...
This takes place in episode 258, actually (the episodes' order changed between the pre-publication in Young Animal and the release of the volume). As for his dialogue, it is as follows:
Sonia: Hunters are always alone? Walking all by themselves through the mountains and forests?
Irvine: There are some who aren't, but I'm alone. I hunt by myself.
Irvine: For days you continue to hunt your prey, running through the wilderness.
Irvine: You hide alone deep in the forest.
Irvine: Night after night, until you lose any sense of time, and then...
Sonia: and then?
Irvine: ....before you know it, you have become an animal yourself.
Considering Miura warmed up his Guts skills with I think three distinct Guts Flashbacks as we were finishing up the Rickert in Falconia story-line.
I don't understand that sentence at all.