Passley joined Pompey on loan from Fulham in January 2015 but was guilty of poor timekeeping on several occasions during his PO4 stay.
The Westleigh Park new boy revealed it was a tough period for him on a personal level, with 'family issues' to be taken care of.
But the 26-year-old, who has signed a two-year deal with Paul Doswell’s side after leaving Dover, refuses to use those problems as an ‘excuse’ for his actions and at the time apologised to the club and Awford for his poor punctuality.
Passley said: ‘I had a couple of family issues which I was dealing with (while at Pompey). It’s not an excuse for me being late or my attitude towards certain things - I hold my hands up and I made mistakes.
‘I made things tough for myself, really. It was self-sabotage.
‘I apologised at the time, it happens, I can’t do anything about it or change it. But I just have to move on with it, really.
‘I’ve apologised to Andy Awford and all the staff at the time - I just try to move on.’
Passley, who made just 12 Blues appearances, saw his south coast spell cut short after suffering concussion in a 3-1 league defeat at Morecambe in April 2015.
Yet, despite what was a difficult period for him, he remains thankful for the experience.
He added: ‘There was a great group of lads at Pompey. I learnt a lot, made some good friendships there and I’ve got some fond memories.
‘I went to Morecambe and I got concussed as well. It started off well but it didn’t end great, but I’m thankful for the experience.’