PAL also build 2 KCR 60 at the same time...but the complexity of AH140 makes those comparison of PKR and LPD looks pale imo,LPD and PKR at the same time is still possible in the past.
PAL LPD is actually smaller than the AH140 which is basically a destroyer in all but name.
so consider we don't build 2 LPD at the same time, I don't think we'll ever build 2 destroyer at the same time either.
but that's just my opinion.