Just a heads up -- I just got back from Lisbon and Tram 28 is running only part of its route. To quote from the Carris website: "From July 29, 2024, Tram 28E will only run between Martim Moniz and Praça Luís de Camões. The route between Camões and Campo de Ourique (Prazeres) is temporarily suspended." https://www.carris.pt/en/travel/alteracoes-de-servico/os-do-179-2024-28e-temporary-change-of-service/
Also there seems to be semi-permament sign outside the ticket booth for the cloister of the Jeronimos Monastery (which is in the park across the street) that says that the wait is 2 hours. We asked the people working the booth if that was accurate, and they said it might even be 3 hours. Fortunately, I bought a ticket anyway. The wait was about 40 minutes (this was at around 11am on a weekday). So don't believe everything your read (or hear). Also if you buy timed tickets in advance, know that the times are meaningless. Everyone waits on the same line for the cloister (which is separate and longer than the line to see the free church). Also be aware that they are doing rehab in the church, so you won't get much of a view of the tombs.
Hope this helps!