Bingowings said:

I was under the impression that the Hoth base wasn't the entire Rebel Alliance (it's just a small band of freedom fighters) after Yavin they split up a grew in number. That way the fleet massing at the end of ESB and getting bigger by ROTJ makes sense (where were these other ships if the whole Alliance operation had just moved from Yavin to Hoth?).

So (if that is the case) Leia isn't in charge of the whole Alliance just the small band on Hoth.

I know the crawl says Luke is in command but that doesn't tally with anything we see in the film (possibly that should change to make sense of what we actually see).

The Battle of Hoth was a big catalyst to the Rebellion getting to the size that it did. For example, the Mon Calamari did not join the Rebellion until the time in between Empire and Jedi. They are the race who brought those big star cruisers to the Battle of Endor.

And yes, the crawl does suggest that Luke is the leader. I think it was hyperbolic thinking, shocking as it might be that GL would allow himself to be self-contradictory! It's been suggested that GL and only GL wrote all of the crawls for all of the movies.

Explains a lot.