Oh no no no, I know it's not a mailbox per se, sorry, I didn't explain this very well...
I literally just need a means to filter emails from all the people within this group so I can quickly search through them for information I may need at any given time in the future in connection with an ongoing situation.
I did use to have a smart mailbox where I had added all our email addresses and included received/sent etc. so that anything to do with this group was filtered in there, adding new addresses as and when, but as I said above, it just vanished!
I'm sure there's a way to find out where it went and get it back but I haven't had the time to figure this out and needed to be able to get to these emails quickly so I used the VIP feature in the meantime and was just trying to find out if there was a way for my sent emails (to VIPs) to be filtered in there too, before they were answered and without adding myself as a VIP so that ALL my other (unrelated) emails wouldn't end up in there too!
I'll look into trying to find my smart mailbox when I have a bit more time but I'm also always a bit afraid of losing important emails (I have in the past) when messing with things like rebuilding mailboxes etc.!
Thank you!