Can someone explain why there are 2 different prepositions. The basic meaning appears to be the same in the example sentences. There are only 6000 search hits on Google for the phrase "plan of going" compared to 6,000,000 for "plan on going" but they are enough to to make me think. Is there a grammar rule that I just can't see?
I'm not against your plan of going to Morocco.
I plan on going to Loterie Farms via Royal Caribbean shore excursion next month.