I'm trying to figure this out?

Okay so about a month ago this guy blocked my number on his iphone through the iphone (the block caller feature). I knew he blocked me because he wasn't responding to texts and for a month when I would call it would ring once or twice and then go straight to voicemail. Well Monday for whatever reason I tried calling him and it rang 4 times. I knew my number was unblocked so I texted saying sorry. No response. Well last night I thought to give him a call and it rang twice and he picked up and said "hello" so I said "joe?" There was no response but he didn't hang up we were still on the line and then I hung up. I texted him twice the first time it said delivered the second text said "sent as text message." So I have a few questions.

1. If he got a new iphone but has the same number, would my number still automatically be blocked?
2. If the text says "sent as text message" did he block my number again? Anytime I would try to send a text in the last month when my number was blocked, they always said "delivered"
3. If he unblocked my number himself, why wouldn't he respond to my texts?

I'm just trying to figure out if he unblocked my number or if maybe he got a new phone? But it's still the same number so I would assume I would still be blocked regardless.

No idea, though i think you should get the message that he does not want to be associated with you, and continuing to do what you are doing will only make the situation worse.