Yes he can get his "privileges" back.
It seems a bit tighter nowadays in the UK - as said above - if you resign (and if you subsequently would not have been removed anyway - BoE's are supposed to look at resignations of those who jump before they're pushed and ask themselves whether they would have removed the resigner had he stayed!) for over a year you will usually have to be an MS first. But you can often be an elder within 6 months to a year of that if your body like you.
If you are removed you have to be an MS first. If you are reproved and removed then you have to wait at least 3 years to be an MS first and usually (if there was no notoriety) it will be about 5 - 7 before you could be an elder from reproof date. If you are DF'd then it's a minimum of 5 years to be an MS from reinstatement and probably approaching a total of 7 - 9 to be an elder again.
In around about 2000(?) a procedure was brought in where "your kids could bring you down" - say you've got 4 kids living at home and one goes bad in jw terms - then unless the body really hate you you'll survive. (But they'll check if your family study was regular and if you ignored previous counsel to get junior in line then you might well be on your way.) If two kids "go bad" then you might lose your privs. If three, then it don't look good, buddy! And if all 4 go out then you're definitely gonna be toast!
I did hear rumour of a guy in Cornwall, England who couldn't cope with "the judicial stuff" but was prepared to be an MS and his body were enlightened enough to ask the branch in the UK who then allowed it in the late 1990's early 2000's but I cannot confirm that as I got it from a prominent know it all elder who seemed to be about 80% right in what he blabbed to me.