We landed ahead of TAP on that day in CPH. Rwy in use 30, which is quite unusual and only used in gusty NW winds. Challenging landing with said gusty conditions. As we were asking for pushback some 35-40 min later we were asked to hold the push due to a "situation" at the airport. We listened in to twr freq and heard TAP being vectored for a second approach on 22L (winds had calmed a bit). TAP stated 107 or 109 souls onboard and having flown from LIS to CPH with that load I doubt they were especially heavy. Once TAP landed (normally) we were pushed back and as we requested taxi, we were to taxi and hold short of taxiway Y to let TAP pass ahead. We got a good look at the aircraft (with rescue services in tow) and the reverser on engine nr.1 was clearly not in the stowed position.