My partner Steve also had paroxysmal AF which increased in frequency from once every 5 weeks or so to several times each week which was when he opted for an ablation. Since his op (which was in 2016) he has had no further instances of AF and now runs just as competitively albeit with a few more years on the clock. He did have further tests in 2018 as he would sometimes experience a flutter which he put down to rogue impulses which could no longer get through the scar tissue around his pulmonary veins. He was given the all clear.
Immediately after his op he recce'd the Oldham Way Ultra with me and deliberately wore his walking boots so that he would not be tempted to run. From memory, he was back running after 5-6 weeks.
Good luck,