[Old Teufel Hunden]

"siege at Westerly Rock"

I'm guessing you mean Casterly Rock. In episode 3 it was confusing because they showed the Lannister Army on the march right after they showed the unsullied taking Casterly Rock, but I believe the Lannister army was actually marching towards High Garden at that point. The only thing that was at Casterly Rock was a small force to guard the castle and Yuron's navy taking out the ships that brought the unsullied there.

I don't believe there is any other siege going on. As far as I can see, Cersei is in big trouble, because the only Army she had that we are aware of is the one that just got torched (literally) and it looks like the survivors in next week's preview are being told to "bend the knee" so they may be rolled into Danareys army. However, it was noted that the money made it to Kings landing so perhaps she can borrow more money from the iron bank and when you have money, you can always get an army...

[Snickering Hound]

I don't believe there is any other siege going on. As far as I can see, Cersei is in big trouble, because the only Army she had that we are aware of is the one that just got torched (literally) and it looks like the survivors in next week's preview are being told to "bend the knee" so they may be rolled into Danareys army. However, it was noted that the money made it to Kings landing so perhaps she can borrow more money from the iron bank and when you have money, you can always get an army...

I wouldn't be surprised that now that the Iron Bank has got their money back, they'll support Daenerys instead.

[calljack]

The ones that got torched were the “stragglers” the main force had already delivered the gold to the castle.

[Impy]

Casterly Rock is so epic in the books, I knew the show version wouldn’t measure up but still...it was just an average castle on a hill.