I've noticed that most large ships get stuck when they get anywhere close to shore now, particularly on the PG map since it is generally much shallower than Caucasus... I'm guessing it's related to this change in 2.5.6.60645:
"Ships placed in shallow water vanish - fixed."
There's no easy way in the ME to figure out where large ships are able to operate, either. Areas close in to shore in the PG map generally have a depth of 10+ meters according to:
https://www.oceangrafix.com/chart/detail/62032-Persian-Gulf
The Type 071 (China) has a draft (draught) of 7m while the Tarawa runs slightly deeper at almost 8m, so the "shallow" water limitation really hampers their utility as Amphibious Assault Ships, especially when scripting. At a minimum, these ships should be allowed to operate in shallow water, and it would probably be better to just put the control in the Mission Designer's hands to better allow ALL ships to transit in and out of "port" areas.