Have NC'ed, please don't out me if you guess. I left ExH nearly 8 years ago as he was aggressive and emotionally abusive and since a couple of months after he hasn't seen DS at all or even been in contact bar birthday cards for the first 3 years (which then tailed off). It was his choice, although he blames me (as I wouldn't just hand over DS after he used contact time as a chance to play mind games so I insisted on supervised contact), and I haven't tried to keep up contact with him. I moved several times after that but my parents lived at the same address as they had for years before (which he still had as that's where he sent the cards), so I always felt I was justified in not being the one who had to make contact iyswim, as he knew where I was and I hadn't actually stopped him contacting us or seeing DS.
Only now my parents have moved last week (had to get council house transfer) so if exh did try to contact us (however unlikely) he could rightly say he couldn't get in touch. And DS has been asking if we can try and 'find my dad and see if he's got time to see me' (I never knew where exh had moved to and despite me explaining age-appropriately that exh had the choice to see DS and chose not to DS still thinks his dad has an excuse, like being busy, and will turn up one day). I never knew where exh had moved to but after DS asking I spent ages searching on the net and managed to find an email address for him, so I could contact him if I wanted.
I feel like I should contact him, for DS's sake and so he can't turn round and throw the non-contact back in my face one day, but I don't know if I should, if it'll create more problems for all of us (if exh is still an arse), if I've left it far too late (DS is nearly 11 but has mild SN so has maturity of 8-9), if I should leave it longer or how to approach it at all.